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<?xml version="1.0" encoding="utf-8"?>
<feed xmlns="http://www.w3.org/2005/Atom">
<title>白生也的成长小站</title>
<link href="http://example.com/atom.xml" rel="self"/>
<link href="http://example.com/"/>
<updated>2022-09-25T03:26:10.913Z</updated>
<id>http://example.com/</id>
<author>
<name>白生也</name>
</author>
<generator uri="https://hexo.io/">Hexo</generator>
<entry>
<title>Hello World</title>
<link href="http://example.com/2022/09/25/hexo/hello-world/"/>
<id>http://example.com/2022/09/25/hexo/hello-world/</id>
<published>2022-09-25T03:26:10.912Z</published>
<updated>2022-09-25T03:26:10.913Z</updated>
<content type="html"><![CDATA[<p>Welcome to <a href="https://hexo.io/">Hexo</a>! This is your very first post. Check <a href="https://hexo.io/docs/">documentation</a> for more info. If you get any problems when using Hexo, you can find the answer in <a href="https://hexo.io/docs/troubleshooting.html">troubleshooting</a> or you can ask me on <a href="https://github.com/hexojs/hexo/issues">GitHub</a>.</p><h2 id="Quick-Start">Quick Start</h2><h3 id="Create-a-new-post">Create a new post</h3><figure class="highlight bash"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line">$ hexo new <span class="string">"My New Post"</span></span><br></pre></td></tr></table></figure><p>More info: <a href="https://hexo.io/docs/writing.html">Writing</a></p><h3 id="Run-server">Run server</h3><figure class="highlight bash"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line">$ hexo server</span><br></pre></td></tr></table></figure><p>More info: <a href="https://hexo.io/docs/server.html">Server</a></p><h3 id="Generate-static-files">Generate static files</h3><figure class="highlight bash"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line">$ hexo generate</span><br></pre></td></tr></table></figure><p>More info: <a href="https://hexo.io/docs/generating.html">Generating</a></p><h3 id="Deploy-to-remote-sites">Deploy to remote sites</h3><figure class="highlight bash"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line">$ hexo deploy</span><br></pre></td></tr></table></figure><p>More info: <a href="https://hexo.io/docs/one-command-deployment.html">Deployment</a></p>]]></content>
<summary type="html"><p>Welcome to <a href="https://hexo.io/">Hexo</a>! This is your very first post. Check <a href="https://hexo.io/docs/">documentation</a> for</summary>
<category term="Hexo" scheme="http://example.com/categories/Hexo/"/>
</entry>
<entry>
<title>4312-出现次数</title>
<link href="http://example.com/2022/07/16/algorithm/Acwing/WeeklyMatches/WeeklyMatches42/4312-%E5%87%BA%E7%8E%B0%E6%AC%A1%E6%95%B0/"/>
<id>http://example.com/2022/07/16/algorithm/Acwing/WeeklyMatches/WeeklyMatches42/4312-%E5%87%BA%E7%8E%B0%E6%AC%A1%E6%95%B0/</id>
<published>2022-07-16T03:25:18.946Z</published>
<updated>2022-07-16T12:00:01.670Z</updated>
<content type="html"><![CDATA[<h2 id="题目-187">题目</h2><p>给定一个长度为 <code>n</code> 的字符串 <code>S=s1s2…sn</code> 以及一个长度为 <code>m</code> 的字符串 <code>T=t1t2…tm</code>。</p><p>两个字符串都由小写字母构成。</p><p>用 <code>s[l,r]</code> 来表示字符串 <code>S</code> 的子串 <code>slsl+1…sr</code>。</p><p>有 <code>q</code> 个询问，每个询问给出两个整数 <code>li,ri``（1≤li≤ri≤n）</code>，请你计算字符串 <code>T</code> 在 <code>s[li,ri] </code>中作为子串出现了多少次。</p><p>例如，字符串 <code>abacabadabacaba</code> 中共包含 <code>4</code> 个子串 <code>ba</code>，所以 <code>ba</code> 在 <code>abacabadabacaba</code> 中作为子串出现了 <code>4</code> 次。</p><h2 id="输入格式-176">输入格式</h2><p>第一行包含三个整数 <code>n,m,q</code>。</p><p>第二行包含一个长度为 <code>n</code> 的由小写字母构成的字符串 <code>S</code>。</p><p>第三行包含一个长度为 <code>m</code> 的由小写字母构成的字符串 <code>T</code>。</p><p>接下来 <code>q</code> 行，每行包含两个整数 <code>li,ri</code>。</p><h2 id="输出格式-176">输出格式</h2><p>每个询问输出一行答案，一个整数，表示出现次数。</p><h2 id="数据范围-202">数据范围</h2><p>前三个测试点满足 <code>1≤n,m,q≤20</code>。<br>所有测试点满足 <code>1≤n,m≤1000，1≤q≤105，1≤li≤ri≤n</code>。</p><h2 id="样例-144">样例</h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br></pre></td><td class="code"><pre><span class="line">输入样例<span class="number">1</span>：</span><br><span class="line"><span class="number">15</span> <span class="number">2</span> <span class="number">3</span></span><br><span class="line">abacabadabacaba</span><br><span class="line">ba</span><br><span class="line"><span class="number">1</span> <span class="number">15</span></span><br><span class="line"><span class="number">3</span> <span class="number">4</span></span><br><span class="line"><span class="number">2</span> <span class="number">14</span></span><br><span class="line">输出样例<span class="number">1</span>：</span><br><span class="line"><span class="number">4</span></span><br><span class="line"><span class="number">0</span></span><br><span class="line"><span class="number">3</span></span><br><span class="line">输入样例<span class="number">2</span>：</span><br><span class="line"><span class="number">3</span> <span class="number">5</span> <span class="number">2</span></span><br><span class="line">aaa</span><br><span class="line">baaab</span><br><span class="line"><span class="number">1</span> <span class="number">3</span></span><br><span class="line"><span class="number">1</span> <span class="number">1</span></span><br><span class="line">输出样例<span class="number">2</span>：</span><br><span class="line"><span class="number">0</span></span><br><span class="line"><span class="number">0</span></span><br></pre></td></tr></table></figure><h2 id="分析-153">分析</h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line">利用前缀和预处理出来从第<span class="number">1</span>个字符到第r个字符有多少个字串符合条件，然后前缀和做差</span><br></pre></td></tr></table></figure><h2 id="解答-205">解答</h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br><span class="line">24</span><br><span class="line">25</span><br><span class="line">26</span><br><span class="line">27</span><br><span class="line">28</span><br><span class="line">29</span><br><span class="line">30</span><br><span class="line">31</span><br><span class="line">32</span><br><span class="line">33</span><br><span class="line">34</span><br><span class="line">35</span><br><span class="line">36</span><br><span class="line">37</span><br><span class="line">38</span><br></pre></td><td class="code"><pre><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><iostream></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><cstring></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><algorithm></span></span></span><br><span class="line"></span><br><span class="line"><span class="keyword">using</span> <span class="keyword">namespace</span> std;</span><br><span class="line"></span><br><span class="line"><span class="type">const</span> <span class="type">int</span> N = <span class="number">1010</span>;</span><br><span class="line"></span><br><span class="line">string str,subStr;</span><br><span class="line"><span class="type">int</span> s[N];</span><br><span class="line"></span><br><span class="line"><span class="function"><span class="type">int</span> <span class="title">main</span><span class="params">()</span></span></span><br><span class="line"><span class="function"></span>{</span><br><span class="line"> <span class="type">int</span> n,m,q;</span><br><span class="line"> <span class="built_in">scanf</span>(<span class="string">"%d%d%d"</span>, &n, &m, &q);</span><br><span class="line"> </span><br><span class="line"> cin>>str>>subStr;</span><br><span class="line"> str=<span class="string">' '</span>+str;</span><br><span class="line"> </span><br><span class="line"> <span class="keyword">for</span> (<span class="type">int</span> i = m; i <= n; i ++ ){</span><br><span class="line"> <span class="keyword">if</span>(str.<span class="built_in">substr</span>(i,m)==subStr)</span><br><span class="line"> s[i]=s[i<span class="number">-1</span>]+<span class="number">1</span>;</span><br><span class="line"> <span class="keyword">else</span></span><br><span class="line"> s[i]=s[i<span class="number">-1</span>]; </span><br><span class="line"> }</span><br><span class="line"> </span><br><span class="line"> <span class="keyword">while</span>(q--){</span><br><span class="line"> <span class="type">int</span> l,r;</span><br><span class="line"> <span class="built_in">scanf</span>(<span class="string">"%d%d"</span>, &l, &r);</span><br><span class="line"> </span><br><span class="line"> <span class="type">int</span> ans=s[r]-s[l<span class="number">-1</span>+m<span class="number">-1</span>];</span><br><span class="line"> </span><br><span class="line"> <span class="built_in">printf</span>(<span class="string">"%d\n"</span>,ans);</span><br><span class="line"> }</span><br><span class="line"> </span><br><span class="line"> <span class="keyword">return</span> <span class="number">0</span>;</span><br><span class="line"> </span><br><span class="line">}</span><br></pre></td></tr></table></figure>]]></content>
<summary type="html"><h2 id="题目-187">题目</h2>
<p>给定一个长度为 <code>n</code> 的字符串 <code>S=s1s2…sn</code> 以及一个长度为 <code>m</code> 的字符串 <code>T=t1t2…tm</code>。</p>
<p>两个字</summary>
<category term="算法" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/"/>
<category term="Acwing" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/Acwing/"/>
<category term="Acwing周赛" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/Acwing/Acwing%E5%91%A8%E8%B5%9B/"/>
</entry>
<entry>
<title>4311-最小值</title>
<link href="http://example.com/2022/07/16/algorithm/Acwing/WeeklyMatches/WeeklyMatches42/4311-%E6%9C%80%E5%B0%8F%E5%80%BC/"/>
<id>http://example.com/2022/07/16/algorithm/Acwing/WeeklyMatches/WeeklyMatches42/4311-%E6%9C%80%E5%B0%8F%E5%80%BC/</id>
<published>2022-07-16T03:25:18.944Z</published>
<updated>2022-07-16T12:26:13.838Z</updated>
<content type="html"><![CDATA[<h2 id="题目-186">题目</h2><p>给定一个正整数 <code>m</code> 和 <code>n</code> 个分数 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><msub><mi>a</mi><mn>1</mn></msub><msub><mi>b</mi><mn>1</mn></msub><mo separator="true">,</mo><msub><mi>a</mi><mn>2</mn></msub><msub><mi>b</mi><mn>2</mn></msub><mo separator="true">,</mo><mo>…</mo><mo separator="true">,</mo><msub><mi>a</mi><mi>n</mi></msub><msub><mi>b</mi><mi>n</mi></msub></mrow><annotation encoding="application/x-tex">a_1b_1,a_2b_2,…,a_nb_n</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.8889em;vertical-align:-0.1944em;"></span><span class="mord"><span class="mord mathnormal">a</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3011em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">1</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mord"><span class="mord mathnormal">b</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3011em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">1</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord mathnormal">a</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3011em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">2</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mord"><span class="mord mathnormal">b</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3011em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">2</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="minner">…</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord mathnormal">a</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.1514em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">n</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mord"><span class="mord mathnormal">b</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.1514em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">n</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span></span></span></span>。</p><p>请你计算 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>m</mi><mo>×</mo><mi>m</mi><mi>i</mi><mi>n</mi><mo stretchy="false">(</mo><mfrac><msub><mi>a</mi><mn>1</mn></msub><msub><mi>b</mi><mn>1</mn></msub></mfrac><mo separator="true">,</mo><mfrac><msub><mi>a</mi><mn>2</mn></msub><msub><mi>b</mi><mn>2</mn></msub></mfrac><mo separator="true">,</mo><mo>…</mo><mo separator="true">,</mo><mfrac><msub><mi>a</mi><mi>n</mi></msub><msub><mi>b</mi><mi>n</mi></msub></mfrac><mo stretchy="false">)</mo></mrow><annotation encoding="application/x-tex">m×min(\frac{a_1}{b_1} ,\frac{a_2}{b_2},…,\frac{a_n}{b_n})</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.6667em;vertical-align:-0.0833em;"></span><span class="mord mathnormal">m</span><span class="mspace" style="margin-right:0.2222em;"></span><span class="mbin">×</span><span class="mspace" style="margin-right:0.2222em;"></span></span><span class="base"><span class="strut" style="height:1.1951em;vertical-align:-0.4451em;"></span><span class="mord mathnormal">min</span><span class="mopen">(</span><span class="mord"><span class="mopen nulldelimiter"></span><span class="mfrac"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.7115em;"><span style="top:-2.655em;"><span class="pstrut" style="height:3em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight"><span class="mord mtight"><span class="mord mathnormal mtight">b</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3173em;"><span style="top:-2.357em;margin-left:0em;margin-right:0.0714em;"><span class="pstrut" style="height:2.5em;"></span><span class="sizing reset-size3 size1 mtight"><span class="mord mtight">1</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.143em;"><span></span></span></span></span></span></span></span></span></span><span style="top:-3.23em;"><span class="pstrut" style="height:3em;"></span><span class="frac-line" style="border-bottom-width:0.04em;"></span></span><span style="top:-3.4101em;"><span class="pstrut" style="height:3em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight"><span class="mord mtight"><span class="mord mathnormal mtight">a</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3173em;"><span style="top:-2.357em;margin-left:0em;margin-right:0.0714em;"><span class="pstrut" style="height:2.5em;"></span><span class="sizing reset-size3 size1 mtight"><span class="mord mtight">1</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.143em;"><span></span></span></span></span></span></span></span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.4451em;"><span></span></span></span></span></span><span class="mclose nulldelimiter"></span></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mopen nulldelimiter"></span><span class="mfrac"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.7115em;"><span style="top:-2.655em;"><span class="pstrut" style="height:3em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight"><span class="mord mtight"><span class="mord mathnormal mtight">b</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3173em;"><span style="top:-2.357em;margin-left:0em;margin-right:0.0714em;"><span class="pstrut" style="height:2.5em;"></span><span class="sizing reset-size3 size1 mtight"><span class="mord mtight">2</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.143em;"><span></span></span></span></span></span></span></span></span></span><span style="top:-3.23em;"><span class="pstrut" style="height:3em;"></span><span class="frac-line" style="border-bottom-width:0.04em;"></span></span><span style="top:-3.4101em;"><span class="pstrut" style="height:3em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight"><span class="mord mtight"><span class="mord mathnormal mtight">a</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3173em;"><span style="top:-2.357em;margin-left:0em;margin-right:0.0714em;"><span class="pstrut" style="height:2.5em;"></span><span class="sizing reset-size3 size1 mtight"><span class="mord mtight">2</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.143em;"><span></span></span></span></span></span></span></span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.4451em;"><span></span></span></span></span></span><span class="mclose nulldelimiter"></span></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="minner">…</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mopen nulldelimiter"></span><span class="mfrac"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.7115em;"><span style="top:-2.655em;"><span class="pstrut" style="height:3em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight"><span class="mord mtight"><span class="mord mathnormal mtight">b</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.1645em;"><span style="top:-2.357em;margin-left:0em;margin-right:0.0714em;"><span class="pstrut" style="height:2.5em;"></span><span class="sizing reset-size3 size1 mtight"><span class="mord mathnormal mtight">n</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.143em;"><span></span></span></span></span></span></span></span></span></span><span style="top:-3.23em;"><span class="pstrut" style="height:3em;"></span><span class="frac-line" style="border-bottom-width:0.04em;"></span></span><span style="top:-3.4101em;"><span class="pstrut" style="height:3em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight"><span class="mord mtight"><span class="mord mathnormal mtight">a</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.1645em;"><span style="top:-2.357em;margin-left:0em;margin-right:0.0714em;"><span class="pstrut" style="height:2.5em;"></span><span class="sizing reset-size3 size1 mtight"><span class="mord mathnormal mtight">n</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.143em;"><span></span></span></span></span></span></span></span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.4451em;"><span></span></span></span></span></span><span class="mclose nulldelimiter"></span></span><span class="mclose">)</span></span></span></span> 的值。</p><h2 id="输入格式-175">输入格式</h2><p>第一行包含两个整数 <code>n,m</code>。</p><p>接下来 <code>n</code> 行，每行包含两个整数 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><msub><mi>a</mi><mi>i</mi></msub><mo separator="true">,</mo><msub><mi>b</mi><mi>i</mi></msub></mrow><annotation encoding="application/x-tex">a_i,b_i</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.8889em;vertical-align:-0.1944em;"></span><span class="mord"><span class="mord mathnormal">a</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">i</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord mathnormal">b</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">i</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span></span></span></span>。</p><h2 id="输出格式-175">输出格式</h2><p>输出一个实数表示结果，结果保留 6 位小数。</p><h2 id="数据范围-201">数据范围</h2><p>前三个测试点满足 <code>1≤n≤50</code>。<br>所有测试点满足 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mn>1</mn><mo>≤</mo><mi>n</mi><mo>≤</mo><mn>5000</mn><mtext>，</mtext><mn>1</mn><mo>≤</mo><mi>m</mi><mo>≤</mo><mn>100</mn><mtext>，</mtext><mn>1</mn><mo>≤</mo><msub><mi>a</mi><mi>i</mi></msub><mo separator="true">,</mo><msub><mi>b</mi><mi>i</mi></msub><mo>≤</mo><mn>100</mn></mrow><annotation encoding="application/x-tex">1≤n≤5000，1≤m≤100，1≤a_i,b_i≤100</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.7804em;vertical-align:-0.136em;"></span><span class="mord">1</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.7719em;vertical-align:-0.136em;"></span><span class="mord mathnormal">n</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.8193em;vertical-align:-0.136em;"></span><span class="mord">5000</span><span class="mord cjk_fallback">，</span><span class="mord">1</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.7719em;vertical-align:-0.136em;"></span><span class="mord mathnormal">m</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.8193em;vertical-align:-0.136em;"></span><span class="mord">100</span><span class="mord cjk_fallback">，</span><span class="mord">1</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.8889em;vertical-align:-0.1944em;"></span><span class="mord"><span class="mord mathnormal">a</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">i</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord mathnormal">b</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">i</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.6444em;"></span><span class="mord">100</span></span></span></span>。</p><h2 id="样例-143">样例</h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br></pre></td><td class="code"><pre><span class="line">输入样例<span class="number">1</span>：</span><br><span class="line"><span class="number">3</span> <span class="number">5</span></span><br><span class="line"><span class="number">1</span> <span class="number">2</span></span><br><span class="line"><span class="number">3</span> <span class="number">4</span></span><br><span class="line"><span class="number">1</span> <span class="number">3</span></span><br><span class="line">输出样例<span class="number">1</span>：</span><br><span class="line"><span class="number">1.666667</span></span><br><span class="line">输入样例<span class="number">2</span>：</span><br><span class="line"><span class="number">2</span> <span class="number">1</span></span><br><span class="line"><span class="number">99</span> <span class="number">100</span></span><br><span class="line"><span class="number">98</span> <span class="number">99</span></span><br><span class="line">输出样例<span class="number">2</span>：</span><br><span class="line"><span class="number">0.989899</span></span><br></pre></td></tr></table></figure><h2 id="分析-152">分析</h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line">遍历一遍计算就行了</span><br></pre></td></tr></table></figure><h2 id="解答-204">解答]</h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br><span class="line">24</span><br><span class="line">25</span><br></pre></td><td class="code"><pre><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><iostream></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><cstring></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><algorithm></span></span></span><br><span class="line"></span><br><span class="line"><span class="keyword">using</span> <span class="keyword">namespace</span> std;</span><br><span class="line"></span><br><span class="line"><span class="type">const</span> <span class="type">double</span> eps = <span class="number">1e-8</span>;</span><br><span class="line"></span><br><span class="line"><span class="function"><span class="type">int</span> <span class="title">main</span><span class="params">()</span></span></span><br><span class="line"><span class="function"></span>{</span><br><span class="line"> <span class="type">int</span> n,m;</span><br><span class="line"> <span class="built_in">scanf</span>(<span class="string">"%d%d"</span>, &n, &m);</span><br><span class="line"> </span><br><span class="line"> <span class="type">double</span> t=<span class="number">200.0</span>;</span><br><span class="line"> <span class="keyword">for</span>(<span class="type">int</span> i=<span class="number">0</span>;i<n;i++){</span><br><span class="line"> <span class="type">int</span> a,b;</span><br><span class="line"> <span class="built_in">scanf</span>(<span class="string">"%d%d"</span>, &a, &b);</span><br><span class="line"> t=<span class="built_in">min</span>(t,a/(<span class="type">double</span>)b);</span><br><span class="line"> }</span><br><span class="line"> <span class="type">double</span> ans=t*m;</span><br><span class="line"> </span><br><span class="line"> <span class="built_in">printf</span>(<span class="string">"%.6lf"</span>,ans);</span><br><span class="line"> </span><br><span class="line"> <span class="keyword">return</span> <span class="number">0</span>;</span><br><span class="line">}</span><br></pre></td></tr></table></figure>]]></content>
<summary type="html"><h2 id="题目-186">题目</h2>
<p>给定一个正整数 <code>m</code> 和 <code>n</code> 个分数 <span class="katex"><span class="katex-mathml"><math xmlns="http://ww</summary>
<category term="算法" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/"/>
<category term="Acwing" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/Acwing/"/>
<category term="Acwing周赛" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/Acwing/Acwing%E5%91%A8%E8%B5%9B/"/>
</entry>
<entry>
<title>4307-数字重排</title>
<link href="http://example.com/2022/07/16/algorithm/Acwing/WeeklyMatches/WeeklyMatches40/4307-%E6%95%B0%E5%AD%97%E9%87%8D%E6%8E%92/"/>
<id>http://example.com/2022/07/16/algorithm/Acwing/WeeklyMatches/WeeklyMatches40/4307-%E6%95%B0%E5%AD%97%E9%87%8D%E6%8E%92/</id>
<published>2022-07-16T03:25:18.939Z</published>
<updated>2022-07-16T12:26:13.838Z</updated>
<content type="html"><![CDATA[<h2 id="题目-182">题目</h2><p>给定两个正整数 <code>a</code> 和 <code>b</code>，均不含前导 <code>0</code>。</p><p>现在，请你对 <code>a</code> 进行重构，重新排列其各位数字顺序，得到一个不含前导 <code>0</code> 的新正整数。</p><p>要求新正整数在不超过 <code>b</code> 的前提下，尽可能大。</p><p>输出新正整数。</p><p>注意，我们允许新正整数等于 <code>a</code>，即保持原样不变。</p><h2 id="输入格式-171">输入格式</h2><p>第一行包含一个正整数 <code>a</code>。</p><p>第二行包含一个正整数 <code>b</code>。</p><p>两个输入数字均不含前导 <code>0</code>。</p><h2 id="输出格式-171">输出格式</h2><p>一个不含前导 <code>0</code> 的正整数，表示答案。</p><p>数据保证一定有解。</p><h2 id="数据范围-197">数据范围</h2><p>前 <code>6</code> 个测试点满足 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mn>1</mn><mo>≤</mo><mi>a</mi><mo separator="true">,</mo><mi>b</mi><mo>≤</mo><mn>1</mn><msup><mn>0</mn><mn>9</mn></msup></mrow><annotation encoding="application/x-tex">1≤a,b≤10^9</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.7804em;vertical-align:-0.136em;"></span><span class="mord">1</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.8889em;vertical-align:-0.1944em;"></span><span class="mord mathnormal">a</span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord mathnormal">b</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.8141em;"></span><span class="mord">1</span><span class="mord"><span class="mord">0</span><span class="msupsub"><span class="vlist-t"><span class="vlist-r"><span class="vlist" style="height:0.8141em;"><span style="top:-3.063em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">9</span></span></span></span></span></span></span></span></span></span></span>。<br>所有测试点满足 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mn>1</mn><mo>≤</mo><mi>a</mi><mo separator="true">,</mo><mi>b</mi><mo>≤</mo><mn>1</mn><msup><mn>0</mn><mn>18</mn></msup></mrow><annotation encoding="application/x-tex">1≤a,b≤10^{18}</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.7804em;vertical-align:-0.136em;"></span><span class="mord">1</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.8889em;vertical-align:-0.1944em;"></span><span class="mord mathnormal">a</span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord mathnormal">b</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.8141em;"></span><span class="mord">1</span><span class="mord"><span class="mord">0</span><span class="msupsub"><span class="vlist-t"><span class="vlist-r"><span class="vlist" style="height:0.8141em;"><span style="top:-3.063em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight"><span class="mord mtight">18</span></span></span></span></span></span></span></span></span></span></span></span>。</p><h2 id="样例-139">样例</h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br></pre></td><td class="code"><pre><span class="line">输入样例<span class="number">1</span>：</span><br><span class="line"><span class="number">123</span></span><br><span class="line"><span class="number">222</span></span><br><span class="line">输出样例<span class="number">1</span>：</span><br><span class="line"><span class="number">213</span></span><br><span class="line">输入样例<span class="number">2</span>：</span><br><span class="line"><span class="number">3921</span></span><br><span class="line"><span class="number">10000</span></span><br><span class="line">输出样例<span class="number">2</span>：</span><br><span class="line"><span class="number">9321</span></span><br><span class="line">输入样例<span class="number">3</span>：</span><br><span class="line"><span class="number">4940</span></span><br><span class="line"><span class="number">5000</span></span><br><span class="line">输出样例<span class="number">3</span>：</span><br><span class="line"><span class="number">4940</span></span><br></pre></td></tr></table></figure><h2 id="分析-148">分析</h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br></pre></td><td class="code"><pre><span class="line">贪心:</span><br><span class="line"> <span class="built_in">sort</span>(a,a+n);</span><br><span class="line"> 优先选取最大的数字MAX来填充，该空位用MAX所组成的最小的数小于等于target的话那么就可以找到</span><br><span class="line"> MAX不行就用第二、第三...依次尝试</span><br></pre></td></tr></table></figure><h2 id="解答-200">解答</h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br><span class="line">24</span><br><span class="line">25</span><br><span class="line">26</span><br><span class="line">27</span><br><span class="line">28</span><br><span class="line">29</span><br><span class="line">30</span><br><span class="line">31</span><br><span class="line">32</span><br><span class="line">33</span><br><span class="line">34</span><br><span class="line">35</span><br><span class="line">36</span><br><span class="line">37</span><br><span class="line">38</span><br><span class="line">39</span><br><span class="line">40</span><br><span class="line">41</span><br><span class="line">42</span><br><span class="line">43</span><br><span class="line">44</span><br><span class="line">45</span><br><span class="line">46</span><br><span class="line">47</span><br><span class="line">48</span><br><span class="line">49</span><br><span class="line">50</span><br><span class="line">51</span><br><span class="line">52</span><br><span class="line">53</span><br><span class="line">54</span><br></pre></td><td class="code"><pre><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><iostream></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><cstring></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><algorithm></span></span></span><br><span class="line"></span><br><span class="line"><span class="keyword">using</span> <span class="keyword">namespace</span> std;</span><br><span class="line"></span><br><span class="line"><span class="type">const</span> <span class="type">int</span> N = <span class="number">10</span>;</span><br><span class="line"></span><br><span class="line"><span class="type">int</span> cnt[N];<span class="comment">//0~9每个数字还剩多少个</span></span><br><span class="line"></span><br><span class="line"><span class="function">string <span class="title">get_min</span><span class="params">(<span class="type">int</span> x)</span></span></span><br><span class="line"><span class="function"></span>{</span><br><span class="line"> string res = <span class="built_in">to_string</span>(x);</span><br><span class="line"> cnt[x] -- ;</span><br><span class="line"></span><br><span class="line"> <span class="keyword">for</span> (<span class="type">int</span> i = <span class="number">0</span>; i < <span class="number">10</span>; i ++ )</span><br><span class="line"> {</span><br><span class="line"> <span class="type">int</span> j=cnt[i];</span><br><span class="line"> <span class="keyword">while</span>(j--) res+=<span class="built_in">to_string</span>(i);</span><br><span class="line"> }</span><br><span class="line"></span><br><span class="line"> cnt[x] ++ ;</span><br><span class="line"> <span class="keyword">return</span> res;</span><br><span class="line"> </span><br><span class="line">}</span><br><span class="line"></span><br><span class="line"><span class="function"><span class="type">int</span> <span class="title">main</span><span class="params">()</span></span></span><br><span class="line"><span class="function"></span>{</span><br><span class="line"> string a,b;</span><br><span class="line"> cin>>a>>b;</span><br><span class="line"> </span><br><span class="line"> <span class="keyword">if</span>(a.<span class="built_in">size</span>()<b.<span class="built_in">size</span>())</span><br><span class="line"> {</span><br><span class="line"> <span class="built_in">sort</span>(a.<span class="built_in">begin</span>(),a.<span class="built_in">end</span>(),<span class="built_in">greater</span><<span class="type">char</span>>());</span><br><span class="line"> cout<<a<<endl;</span><br><span class="line"> <span class="keyword">return</span> <span class="number">0</span>;</span><br><span class="line"> }</span><br><span class="line"> </span><br><span class="line"> <span class="keyword">for</span> (<span class="keyword">auto</span> x:a ) cnt[x-<span class="string">'0'</span>]++;</span><br><span class="line"> </span><br><span class="line"> string res;</span><br><span class="line"> <span class="keyword">for</span> (<span class="type">int</span> i = <span class="number">0</span>; i < a.<span class="built_in">size</span>(); i ++ )<span class="comment">//枚举每一位</span></span><br><span class="line"> <span class="keyword">for</span> (<span class="type">int</span> j = <span class="number">9</span>; j >= <span class="number">0</span>; j -- )<span class="comment">//在空位上填充合适的数字</span></span><br><span class="line"> <span class="keyword">if</span>(cnt[j]&&res+<span class="built_in">get_min</span>(j)<=b)</span><br><span class="line"> {</span><br><span class="line"> cnt[j]--;</span><br><span class="line"> res+=<span class="built_in">to_string</span>(j);</span><br><span class="line"> <span class="keyword">break</span>;</span><br><span class="line"> }</span><br><span class="line"> </span><br><span class="line"> cout<<res<<endl;</span><br><span class="line"> </span><br><span class="line"> <span class="keyword">return</span> <span class="number">0</span>;</span><br><span class="line">}</span><br></pre></td></tr></table></figure>]]></content>
<summary type="html"><h2 id="题目-182">题目</h2>
<p>给定两个正整数 <code>a</code> 和 <code>b</code>，均不含前导 <code>0</code>。</p>
<p>现在，请你对 <code>a</code> 进行重构，重新排列其各位数字顺序，得到一个不</summary>
<category term="算法" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/"/>
<category term="Acwing" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/Acwing/"/>
<category term="Acwing周赛" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/Acwing/Acwing%E5%91%A8%E8%B5%9B/"/>
</entry>
<entry>
<title>4306-序列处理</title>
<link href="http://example.com/2022/07/16/algorithm/Acwing/WeeklyMatches/WeeklyMatches40/4306-%E5%BA%8F%E5%88%97%E5%A4%84%E7%90%86/"/>
<id>http://example.com/2022/07/16/algorithm/Acwing/WeeklyMatches/WeeklyMatches40/4306-%E5%BA%8F%E5%88%97%E5%A4%84%E7%90%86/</id>
<published>2022-07-16T03:25:18.937Z</published>
<updated>2022-07-16T12:26:15.607Z</updated>
<content type="html"><![CDATA[<h2 id="题目-181">题目</h2><p>给定一个长度为 <code>n</code> 的整数序列 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><msub><mi>a</mi><mn>1</mn></msub><mo separator="true">,</mo><msub><mi>a</mi><mn>2</mn></msub><mo separator="true">,</mo><mo>…</mo><mo separator="true">,</mo><msub><mi>a</mi><mi>n</mi></msub></mrow><annotation encoding="application/x-tex">a_1,a_2,…,a_n</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.625em;vertical-align:-0.1944em;"></span><span class="mord"><span class="mord mathnormal">a</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3011em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">1</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord mathnormal">a</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3011em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">2</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="minner">…</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord mathnormal">a</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.1514em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">n</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span></span></span></span>。</p><p>我们可以对该序列进行修改操作，每次操作选中其中一个元素，并使其增加 <code>1</code>。</p><p>现在，请你计算要使得序列中的元素各不相同，至少需要进行多少次操作。</p><h2 id="输入格式-170">输入格式</h2><p>第一行包含整数 <code>n</code>。</p><p>第二行包含 <code>n</code> 个整数 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><msub><mi>a</mi><mn>1</mn></msub><mo separator="true">,</mo><msub><mi>a</mi><mn>2</mn></msub><mo separator="true">,</mo><mo>…</mo><mo separator="true">,</mo><msub><mi>a</mi><mi>n</mi></msub></mrow><annotation encoding="application/x-tex">a_1,a_2,…,a_n</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.625em;vertical-align:-0.1944em;"></span><span class="mord"><span class="mord mathnormal">a</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3011em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">1</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord mathnormal">a</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3011em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">2</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="minner">…</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord mathnormal">a</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.1514em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">n</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span></span></span></span>。</p><h2 id="输出格式-170">输出格式</h2><p>一个整数，表示所需的最少操作次数。</p><h2 id="数据范围-196">数据范围</h2><p>前 <code>6</code> 个测试点满足 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mn>1</mn><mo>≤</mo><mi>n</mi><mo>≤</mo><mn>10</mn></mrow><annotation encoding="application/x-tex">1≤n≤10</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.7804em;vertical-align:-0.136em;"></span><span class="mord">1</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.7719em;vertical-align:-0.136em;"></span><span class="mord mathnormal">n</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.6444em;"></span><span class="mord">10</span></span></span></span>。<br>所有测试点满足 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mn>1</mn><mo>≤</mo><mi>n</mi><mo>≤</mo><mn>3000</mn><mtext>，</mtext><mn>1</mn><mo>≤</mo><msub><mi>a</mi><mi>i</mi></msub><mo>≤</mo><mi>n</mi></mrow><annotation encoding="application/x-tex">1≤n≤3000，1≤a_i≤n</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.7804em;vertical-align:-0.136em;"></span><span class="mord">1</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.7719em;vertical-align:-0.136em;"></span><span class="mord mathnormal">n</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.8193em;vertical-align:-0.136em;"></span><span class="mord">3000</span><span class="mord cjk_fallback">，</span><span class="mord">1</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.786em;vertical-align:-0.15em;"></span><span class="mord"><span class="mord mathnormal">a</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">i</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.4306em;"></span><span class="mord mathnormal">n</span></span></span></span>。</p><h2 id="样例-138">样例</h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br></pre></td><td class="code"><pre><span class="line">输入样例<span class="number">1</span>：</span><br><span class="line"><span class="number">4</span></span><br><span class="line"><span class="number">1</span> <span class="number">3</span> <span class="number">1</span> <span class="number">4</span></span><br><span class="line">输出样例<span class="number">1</span>：</span><br><span class="line"><span class="number">1</span></span><br><span class="line">输入样例<span class="number">2</span>：</span><br><span class="line"><span class="number">5</span></span><br><span class="line"><span class="number">1</span> <span class="number">2</span> <span class="number">3</span> <span class="number">2</span> <span class="number">5</span></span><br><span class="line">输出样例<span class="number">2</span>：</span><br><span class="line"><span class="number">2</span></span><br></pre></td></tr></table></figure><h2 id="分析-147">分析</h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br></pre></td><td class="code"><pre><span class="line">贪心:</span><br><span class="line"> <span class="built_in">sort</span>(a,a+n);</span><br><span class="line"> 排序之后后一个数大于等于前一个数的，而只有在大于的时候才能实现互不相同</span><br></pre></td></tr></table></figure><h2 id="解答-199">解答</h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br><span class="line">24</span><br><span class="line">25</span><br><span class="line">26</span><br><span class="line">27</span><br><span class="line">28</span><br><span class="line">29</span><br><span class="line">30</span><br></pre></td><td class="code"><pre><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><iostream></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><cstring></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><algorithm></span></span></span><br><span class="line"></span><br><span class="line"><span class="keyword">using</span> <span class="keyword">namespace</span> std;</span><br><span class="line"></span><br><span class="line"><span class="type">const</span> <span class="type">int</span> N = <span class="number">3010</span>;</span><br><span class="line"></span><br><span class="line"><span class="type">int</span> a[N];</span><br><span class="line"><span class="type">int</span> n;</span><br><span class="line"></span><br><span class="line"><span class="function"><span class="type">int</span> <span class="title">main</span><span class="params">()</span></span></span><br><span class="line"><span class="function"></span>{</span><br><span class="line"> cin>>n;</span><br><span class="line"> <span class="keyword">for</span> (<span class="type">int</span> i = <span class="number">0</span>; i < n; i ++ ) cin>>a[i];</span><br><span class="line"> </span><br><span class="line"> <span class="built_in">sort</span>(a,a+n);</span><br><span class="line"> </span><br><span class="line"> <span class="type">int</span> ans=<span class="number">0</span>;</span><br><span class="line"> <span class="keyword">for</span> (<span class="type">int</span> i = <span class="number">1</span>; i < n; i ++ )</span><br><span class="line"> <span class="keyword">while</span>(a[i]<=a[i<span class="number">-1</span>])</span><br><span class="line"> {</span><br><span class="line"> a[i]++;</span><br><span class="line"> ans++;</span><br><span class="line"> }</span><br><span class="line"> </span><br><span class="line"> cout<<ans<<endl;</span><br><span class="line"> </span><br><span class="line"> <span class="keyword">return</span> <span class="number">0</span>;</span><br><span class="line">}</span><br></pre></td></tr></table></figure>]]></content>
<summary type="html"><h2 id="题目-181">题目</h2>
<p>给定一个长度为 <code>n</code> 的整数序列 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/M</summary>
<category term="算法" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/"/>
<category term="Acwing" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/Acwing/"/>
<category term="Acwing周赛" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/Acwing/Acwing%E5%91%A8%E8%B5%9B/"/>
</entry>
<entry>
<title>4305-斐波拉契数列</title>
<link href="http://example.com/2022/07/16/algorithm/Acwing/WeeklyMatches/WeeklyMatches40/4305-%E6%96%90%E6%B3%A2%E6%8B%89%E5%A5%91%E6%95%B0%E5%88%97/"/>
<id>http://example.com/2022/07/16/algorithm/Acwing/WeeklyMatches/WeeklyMatches40/4305-%E6%96%90%E6%B3%A2%E6%8B%89%E5%A5%91%E6%95%B0%E5%88%97/</id>
<published>2022-07-16T03:25:18.934Z</published>
<updated>2022-07-16T12:26:15.607Z</updated>
<content type="html"><![CDATA[<h2 id="题目-179">题目</h2><p>斐波那契数列指的是这样一个数列：<code>1、1、2、3、5、8、13、21、34、……</code><br>在数学上，斐波那契数列以如下递推的形式定义：<code>F(0)=1，F(1)=1,F(n)=F(n−1)+F(n−2)（n≥2，n∈N∗）</code>。</p><p>如果一个数出现在斐波那契数列之中，那么我们就称这个数为斐波那契数。</p><p>现在，给定一个整数 <code>n</code>，请你构造一个长度为 <code>n</code> 的字符串 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><msub><mi>s</mi><mn>1</mn></msub><msub><mi>s</mi><mn>2</mn></msub><mo>…</mo><msub><mi>s</mi><mi>n</mi></msub></mrow><annotation encoding="application/x-tex">s_1s_2…s_n</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.5806em;vertical-align:-0.15em;"></span><span class="mord"><span class="mord mathnormal">s</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3011em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">1</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mord"><span class="mord mathnormal">s</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3011em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">2</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mspace" style="margin-right:0.1667em;"></span><span class="minner">…</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord mathnormal">s</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.1514em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">n</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span></span></span></span>。</p><p>对于字符串中的第 <code>i</code> 个字符 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><msub><mi>s</mi><mi>i</mi></msub></mrow><annotation encoding="application/x-tex">s_i</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.5806em;vertical-align:-0.15em;"></span><span class="mord"><span class="mord mathnormal">s</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">i</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span></span></span></span>：</p><p>如果 <code>i</code> 是斐波那契数，则 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><msub><mi>s</mi><mi>i</mi></msub></mrow><annotation encoding="application/x-tex">s_i</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.5806em;vertical-align:-0.15em;"></span><span class="mord"><span class="mord mathnormal">s</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">i</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span></span></span></span> 为大写字母 <code>O</code>。<br>如果 <code>i</code> 不是斐波那契数，则 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><msub><mi>s</mi><mi>i</mi></msub></mrow><annotation encoding="application/x-tex">s_i</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.5806em;vertical-align:-0.15em;"></span><span class="mord"><span class="mord mathnormal">s</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">i</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span></span></span></span> 为小写字母 <code>o</code>。<br>输出构造好的字符串。</p><p>注意，字符下标从 <code>1</code> 到 <code>n</code>。</p><h2 id="输入格式-168">输入格式</h2><p>一个整数 <code>n</code>。</p><h2 id="输出格式-168">输出格式</h2><p>一个字符串，表示答案。</p><h2 id="数据范围-194">数据范围</h2><p>前三个测试点满足 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mn>1</mn><mo>≤</mo><mi>n</mi><mo>≤</mo><mn>100</mn></mrow><annotation encoding="application/x-tex">1≤n≤100</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.7804em;vertical-align:-0.136em;"></span><span class="mord">1</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.7719em;vertical-align:-0.136em;"></span><span class="mord mathnormal">n</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.6444em;"></span><span class="mord">100</span></span></span></span>。<br>所有测试点满足 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mn>1</mn><mo>≤</mo><mi>n</mi><mo>≤</mo><mn>1000</mn></mrow><annotation encoding="application/x-tex">1≤n≤1000</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.7804em;vertical-align:-0.136em;"></span><span class="mord">1</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.7719em;vertical-align:-0.136em;"></span><span class="mord mathnormal">n</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.6444em;"></span><span class="mord">1000</span></span></span></span>。</p><h2 id="样例-136">样例</h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br></pre></td><td class="code"><pre><span class="line">输入样例<span class="number">1</span>：</span><br><span class="line"><span class="number">8</span></span><br><span class="line">输出样例<span class="number">1</span>：</span><br><span class="line">OOOoOooO</span><br><span class="line">输入样例<span class="number">2</span>：</span><br><span class="line"><span class="number">15</span></span><br><span class="line">输出样例<span class="number">2</span>：</span><br><span class="line">OOOoOooOooooOoo</span><br></pre></td></tr></table></figure><h2 id="分析-145">分析</h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line">预先把<span class="number">1</span>~n之间的斐波拉契数算出来,然后遍历<span class="number">1</span>~n</span><br></pre></td></tr></table></figure><h2 id="解答-197">解答</h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br><span class="line">24</span><br><span class="line">25</span><br><span class="line">26</span><br><span class="line">27</span><br><span class="line">28</span><br><span class="line">29</span><br><span class="line">30</span><br><span class="line">31</span><br><span class="line">32</span><br><span class="line">33</span><br><span class="line">34</span><br><span class="line">35</span><br></pre></td><td class="code"><pre><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><iostream></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><cstring></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><algorithm></span></span></span><br><span class="line"></span><br><span class="line"><span class="keyword">using</span> <span class="keyword">namespace</span> std;</span><br><span class="line"></span><br><span class="line"><span class="type">const</span> <span class="type">int</span> N = <span class="number">1010</span>;</span><br><span class="line"></span><br><span class="line"><span class="type">bool</span> st[N];</span><br><span class="line"><span class="type">int</span> n;</span><br><span class="line"></span><br><span class="line"><span class="function"><span class="type">int</span> <span class="title">main</span><span class="params">()</span></span></span><br><span class="line"><span class="function"></span>{</span><br><span class="line"> cin>>n;</span><br><span class="line"> </span><br><span class="line"> <span class="type">int</span> i0=<span class="number">0</span>,i1=<span class="number">1</span>;</span><br><span class="line"> </span><br><span class="line"> <span class="keyword">while</span>(i0 <= n)</span><br><span class="line"> {</span><br><span class="line"> st[i1]=<span class="literal">true</span>;</span><br><span class="line"> </span><br><span class="line"> <span class="type">int</span> t=i1+i0;</span><br><span class="line"> i0=i1;</span><br><span class="line"> i1=t;</span><br><span class="line"> }</span><br><span class="line"> st[i1]=<span class="literal">true</span>;</span><br><span class="line"> </span><br><span class="line"> <span class="keyword">for</span> (<span class="type">int</span> i = <span class="number">1</span>; i <= n; i ++ )</span><br><span class="line"> <span class="keyword">if</span>(st[i])</span><br><span class="line"> <span class="built_in">printf</span>(<span class="string">"O"</span>);</span><br><span class="line"> <span class="keyword">else</span></span><br><span class="line"> <span class="built_in">printf</span>(<span class="string">"o"</span>);</span><br><span class="line"> </span><br><span class="line"> <span class="keyword">return</span> <span class="number">0</span>;</span><br><span class="line">}</span><br></pre></td></tr></table></figure>]]></content>
<summary type="html"><h2 id="题目-179">题目</h2>
<p>斐波那契数列指的是这样一个数列：<code>1、1、2、3、5、8、13、21、34、……</code><br>
在数学上，斐波那契数列以如下递推的形式定义：<code>F(0)=1，F(1)=1,F(n)=F(n−1)+F(</summary>
<category term="算法" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/"/>
<category term="Acwing" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/Acwing/"/>
<category term="Acwing周赛" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/Acwing/Acwing%E5%91%A8%E8%B5%9B/"/>
</entry>
<entry>
<title>4301-截断序列</title>
<link href="http://example.com/2022/07/16/algorithm/Acwing/WeeklyMatches/WeeklyMatches38/4301-%E6%88%AA%E6%96%AD%E5%BA%8F%E5%88%97/"/>
<id>http://example.com/2022/07/16/algorithm/Acwing/WeeklyMatches/WeeklyMatches38/4301-%E6%88%AA%E6%96%AD%E5%BA%8F%E5%88%97/</id>
<published>2022-07-16T03:25:18.929Z</published>
<updated>2022-07-16T12:26:15.607Z</updated>
<content type="html"><![CDATA[<h2 id="题目-185">题目</h2><p>给定一个由 n 位数字组成的序列 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><msub><mi>a</mi><mn>1</mn></msub><msub><mi>a</mi><mn>2</mn></msub><mo>…</mo><msub><mi>a</mi><mi>n</mi></msub></mrow><annotation encoding="application/x-tex">a_1a_2…a_n</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.5806em;vertical-align:-0.15em;"></span><span class="mord"><span class="mord mathnormal">a</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3011em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">1</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mord"><span class="mord mathnormal">a</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3011em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">2</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mspace" style="margin-right:0.1667em;"></span><span class="minner">…</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord mathnormal">a</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.1514em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">n</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span></span></span></span>。</p><p>其中，每个数字都是 <code>0∼9</code> 之一。</p><p>请你判断，能否将数列从中间截断为两个或更多个非空部分，要求每一部分的各位数字之和都相等。</p><p>例如，<code>350178</code> 可以截断为 <code>3</code> 个部分 <code>350</code>、<code>17</code>、<code>8</code>，并且满足 <code>3+5+0=1+7=8</code>。</p><h2 id="输入格式-174">输入格式</h2><p>第一行包含一个整数 n。</p><p>第二行包含 n 个数字 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><msub><mi>a</mi><mn>1</mn></msub><mo separator="true">,</mo><msub><mi>a</mi><mn>2</mn></msub><mo separator="true">,</mo><mo>…</mo><mo separator="true">,</mo><msub><mi>a</mi><mi>n</mi></msub></mrow><annotation encoding="application/x-tex">a_1,a_2,…,a_n</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.625em;vertical-align:-0.1944em;"></span><span class="mord"><span class="mord mathnormal">a</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3011em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">1</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord mathnormal">a</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3011em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">2</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="minner">…</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord mathnormal">a</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.1514em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">n</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span></span></span></span>，数字之间不含空格。</p><h2 id="输出格式-174">输出格式</h2><p>如果可以按要求截断数列，则输出 <code>YES</code>，否则输出 <code>NO</code>。</p><h2 id="数据范围-200">数据范围</h2><p>前 6 个测试点满足 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mn>2</mn><mo>≤</mo><mi>n</mi><mo>≤</mo><mn>10</mn></mrow><annotation encoding="application/x-tex">2≤n≤10</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.7804em;vertical-align:-0.136em;"></span><span class="mord">2</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.7719em;vertical-align:-0.136em;"></span><span class="mord mathnormal">n</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.6444em;"></span><span class="mord">10</span></span></span></span>。<br>所有测试点满足 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mn>2</mn><mo>≤</mo><mi>n</mi><mo>≤</mo><mn>100</mn><mtext>，</mtext><mn>0</mn><mo>≤</mo><msub><mi>a</mi><mi>i</mi></msub><mo>≤</mo><mn>9</mn></mrow><annotation encoding="application/x-tex">2≤n≤100，0≤a_i≤9</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.7804em;vertical-align:-0.136em;"></span><span class="mord">2</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.7719em;vertical-align:-0.136em;"></span><span class="mord mathnormal">n</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.8193em;vertical-align:-0.136em;"></span><span class="mord">100</span><span class="mord cjk_fallback">，</span><span class="mord">0</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.786em;vertical-align:-0.15em;"></span><span class="mord"><span class="mord mathnormal">a</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">i</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.6444em;"></span><span class="mord">9</span></span></span></span>。</p><h2 id="样例-142">样例</h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br></pre></td><td class="code"><pre><span class="line">输入样例<span class="number">1</span>：</span><br><span class="line"><span class="number">5</span></span><br><span class="line"><span class="number">73452</span></span><br><span class="line">输出样例<span class="number">1</span>：</span><br><span class="line">YES</span><br><span class="line"></span><br><span class="line">输入样例<span class="number">2</span>：</span><br><span class="line"><span class="number">4</span></span><br><span class="line"><span class="number">1248</span></span><br><span class="line">输出样例<span class="number">2</span>：</span><br><span class="line">NO</span><br></pre></td></tr></table></figure><h2 id="分析-151">分析</h2><h4 id="思路">思路</h4><ol><li>假设序列所有位上的数之和是<code>sum</code>，并且可以被分成<code>i</code>段,那么每一段之和就是<code>s=sum/i</code>;</li><li>然后我们就遍历序列，测试是不是能找到一段之和位<code>s</code>的每一段,从头到尾能分出这些段就是<code>YES</code>，否则就是<code>NO</code></li><li>枚举测试分段数:<span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>O</mi><mo stretchy="false">(</mo><mi>n</mi><mo stretchy="false">)</mo></mrow><annotation encoding="application/x-tex">O(n)</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:1em;vertical-align:-0.25em;"></span><span class="mord mathnormal" style="margin-right:0.02778em;">O</span><span class="mopen">(</span><span class="mord mathnormal">n</span><span class="mclose">)</span></span></span></span><br>枚举序列计算s:<span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>O</mi><mo stretchy="false">(</mo><mi>n</mi><mo stretchy="false">)</mo></mrow><annotation encoding="application/x-tex">O(n)</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:1em;vertical-align:-0.25em;"></span><span class="mord mathnormal" style="margin-right:0.02778em;">O</span><span class="mopen">(</span><span class="mord mathnormal">n</span><span class="mclose">)</span></span></span></span><br>总共时间复杂度:<span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>O</mi><mo stretchy="false">(</mo><msup><mi>n</mi><mn>2</mn></msup><mo stretchy="false">)</mo></mrow><annotation encoding="application/x-tex">O(n^2)</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:1.0641em;vertical-align:-0.25em;"></span><span class="mord mathnormal" style="margin-right:0.02778em;">O</span><span class="mopen">(</span><span class="mord"><span class="mord mathnormal">n</span><span class="msupsub"><span class="vlist-t"><span class="vlist-r"><span class="vlist" style="height:0.8141em;"><span style="top:-3.063em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">2</span></span></span></span></span></span></span></span><span class="mclose">)</span></span></span></span></li></ol><h2 id="解答-203">解答</h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br><span class="line">24</span><br><span class="line">25</span><br><span class="line">26</span><br><span class="line">27</span><br><span class="line">28</span><br><span class="line">29</span><br><span class="line">30</span><br><span class="line">31</span><br><span class="line">32</span><br><span class="line">33</span><br><span class="line">34</span><br><span class="line">35</span><br><span class="line">36</span><br><span class="line">37</span><br><span class="line">38</span><br><span class="line">39</span><br><span class="line">40</span><br><span class="line">41</span><br><span class="line">42</span><br><span class="line">43</span><br><span class="line">44</span><br><span class="line">45</span><br><span class="line">46</span><br><span class="line">47</span><br><span class="line">48</span><br><span class="line">49</span><br><span class="line">50</span><br><span class="line">51</span><br></pre></td><td class="code"><pre><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><iostream></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><cstring></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><algorithm></span></span></span><br><span class="line"></span><br><span class="line"><span class="keyword">using</span> <span class="keyword">namespace</span> std;</span><br><span class="line"></span><br><span class="line"><span class="type">const</span> <span class="type">int</span> N = <span class="number">110</span>;</span><br><span class="line"></span><br><span class="line"><span class="type">char</span> a[N];</span><br><span class="line"><span class="type">int</span> n;</span><br><span class="line"></span><br><span class="line"><span class="function"><span class="type">int</span> <span class="title">to_num</span><span class="params">(<span class="type">char</span> ch)</span></span></span><br><span class="line"><span class="function"></span>{</span><br><span class="line"> <span class="keyword">return</span> ch-<span class="string">'0'</span>;</span><br><span class="line">}</span><br><span class="line"></span><br><span class="line"><span class="function"><span class="type">int</span> <span class="title">main</span><span class="params">()</span></span></span><br><span class="line"><span class="function"></span>{</span><br><span class="line"> cin>>n;</span><br><span class="line"> cin>>a;</span><br><span class="line"> </span><br><span class="line"> <span class="type">int</span> sum=<span class="number">0</span>;</span><br><span class="line"> <span class="keyword">for</span> (<span class="type">int</span> i = <span class="number">0</span>; i < n; i ++ )</span><br><span class="line"> sum+=<span class="built_in">to_num</span>(a[i]);</span><br><span class="line"> </span><br><span class="line"> </span><br><span class="line"> <span class="keyword">for</span> (<span class="type">int</span> i = <span class="number">2</span>; i <= n; i ++ )</span><br><span class="line"> {</span><br><span class="line"> <span class="keyword">if</span>(sum%i!=<span class="number">0</span>) <span class="keyword">continue</span>;</span><br><span class="line"> <span class="type">bool</span> flag=<span class="literal">true</span>;</span><br><span class="line"> <span class="type">int</span> k=<span class="number">0</span>;</span><br><span class="line"> <span class="keyword">for</span> (<span class="type">int</span> j = <span class="number">0</span>; j < n; j ++ )</span><br><span class="line"> {</span><br><span class="line"> k+=<span class="built_in">to_num</span>(a[j]);</span><br><span class="line"> <span class="keyword">if</span>(sum/i==k){</span><br><span class="line"> k=<span class="number">0</span>;</span><br><span class="line"> }</span><br><span class="line"> <span class="keyword">else</span> <span class="keyword">if</span>(sum/i<k){</span><br><span class="line"> flag=<span class="literal">false</span>;</span><br><span class="line"> <span class="keyword">break</span>;</span><br><span class="line"> }</span><br><span class="line"> }</span><br><span class="line"> <span class="keyword">if</span>(flag){</span><br><span class="line"> <span class="built_in">puts</span>(<span class="string">"YES"</span>);</span><br><span class="line"> <span class="keyword">return</span> <span class="number">0</span>;</span><br><span class="line"> } </span><br><span class="line"> }</span><br><span class="line"> </span><br><span class="line"> <span class="built_in">puts</span>(<span class="string">"NO"</span>);</span><br><span class="line"> <span class="keyword">return</span> <span class="number">0</span>;</span><br><span class="line">}</span><br></pre></td></tr></table></figure>]]></content>
<summary type="html"><h2 id="题目-185">题目</h2>
<p>给定一个由 n 位数字组成的序列 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"></summary>
<category term="算法" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/"/>
<category term="Acwing" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/Acwing/"/>
<category term="Acwing周赛" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/Acwing/Acwing%E5%91%A8%E8%B5%9B/"/>
</entry>
<entry>
<title>4300-两种操作</title>
<link href="http://example.com/2022/07/16/algorithm/Acwing/WeeklyMatches/WeeklyMatches38/4300-%E4%B8%A4%E7%A7%8D%E6%93%8D%E4%BD%9C/"/>
<id>http://example.com/2022/07/16/algorithm/Acwing/WeeklyMatches/WeeklyMatches38/4300-%E4%B8%A4%E7%A7%8D%E6%93%8D%E4%BD%9C/</id>
<published>2022-07-16T03:25:18.927Z</published>
<updated>2022-07-16T12:26:15.608Z</updated>
<content type="html"><![CDATA[<h2 id="题目-184">题目</h2><p>给定一个正整数 <code>n</code>，我们希望你可以通过一系列的操作，将其变为另一个正整数 <code>m</code>。<br>操作共分两种：</p><ol><li>将当前的数乘以 <code>2</code>。</li><li>将当前的数减去 <code>1</code>。<br>要求，在变换过程中，数字始终为正。</li></ol><p>请你计算，所需要的最少操作次数。</p><h2 id="输入格式-173">输入格式</h2><p>一行，两个不同的正整数 <code>n</code> 和 <code>m</code>。</p><h2 id="输出格式-173">输出格式</h2><p>一个整数，表示所需的最少操作次数。</p><h2 id="数据范围-199">数据范围</h2><p>前 <code>6</code> 个测试点满足 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mn>1</mn><mo>≤</mo><mi>n</mi><mo separator="true">,</mo><mi>m</mi><mo>≤</mo><mn>10</mn></mrow><annotation encoding="application/x-tex">1≤n,m≤10</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.7804em;vertical-align:-0.136em;"></span><span class="mord">1</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.8304em;vertical-align:-0.1944em;"></span><span class="mord mathnormal">n</span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord mathnormal">m</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.6444em;"></span><span class="mord">10</span></span></span></span>。<br>所有测试点满足 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mn>1</mn><mo>≤</mo><mi>n</mi><mo separator="true">,</mo><mi>m</mi><mo>≤</mo><mn>10000</mn></mrow><annotation encoding="application/x-tex">1≤n,m≤10000</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.7804em;vertical-align:-0.136em;"></span><span class="mord">1</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.8304em;vertical-align:-0.1944em;"></span><span class="mord mathnormal">n</span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord mathnormal">m</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.6444em;"></span><span class="mord">10000</span></span></span></span>。</p><h2 id="样例-141">样例</h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br></pre></td><td class="code"><pre><span class="line">输入样例<span class="number">1</span>：</span><br><span class="line"><span class="number">4</span> <span class="number">6</span></span><br><span class="line">输出样例<span class="number">1</span>：</span><br><span class="line"><span class="number">2</span></span><br><span class="line"></span><br><span class="line">输入样例<span class="number">2</span>：</span><br><span class="line"><span class="number">10</span> <span class="number">1</span></span><br><span class="line">输出样例<span class="number">2</span>：</span><br><span class="line"><span class="number">9</span></span><br></pre></td></tr></table></figure><h2 id="分析-150">分析</h2><h4 id="贪心思路">贪心思路</h4><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">if</span> end比start要小: 那就只能减一达到目的</span><br><span class="line">如果不是:</span><br><span class="line"> 就一直让end减小直到小于<span class="built_in">start</span></span><br><span class="line"> (对应到题目的操作就end有两种变换方式:/<span class="number">2</span>、+<span class="number">1</span>)</span><br><span class="line"> <span class="keyword">if</span> end是奇数就+<span class="number">1</span></span><br><span class="line"> 一直减小</span><br><span class="line">然后就只能减一达到目的</span><br></pre></td></tr></table></figure><h2 id="解答-202">解答</h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br><span class="line">24</span><br><span class="line">25</span><br><span class="line">26</span><br><span class="line">27</span><br><span class="line">28</span><br><span class="line">29</span><br><span class="line">30</span><br><span class="line">31</span><br><span class="line">32</span><br></pre></td><td class="code"><pre><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><iostream></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><cstring></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><algorithm></span></span></span><br><span class="line"></span><br><span class="line"><span class="keyword">using</span> <span class="keyword">namespace</span> std;</span><br><span class="line"></span><br><span class="line"><span class="function"><span class="type">int</span> <span class="title">main</span><span class="params">()</span></span></span><br><span class="line"><span class="function"></span>{</span><br><span class="line"> <span class="type">int</span> l,r;</span><br><span class="line"> cin>>l>>r;</span><br><span class="line"> </span><br><span class="line"> <span class="keyword">if</span>(r<l){</span><br><span class="line"> cout<<l-r<<endl;</span><br><span class="line"> <span class="keyword">return</span> <span class="number">0</span>;</span><br><span class="line"> }</span><br><span class="line"> </span><br><span class="line"> <span class="type">int</span> ans=<span class="number">0</span>;</span><br><span class="line"> <span class="keyword">while</span>(l<r){</span><br><span class="line"> <span class="keyword">if</span>(r&<span class="number">1</span>){</span><br><span class="line"> r+=<span class="number">1</span>;</span><br><span class="line"> ans++;</span><br><span class="line"> }</span><br><span class="line"> r>>=<span class="number">1</span>;</span><br><span class="line"> ans++;</span><br><span class="line"> }</span><br><span class="line"> </span><br><span class="line"> ans+=l-r;</span><br><span class="line"> </span><br><span class="line"> cout<<ans<<endl;</span><br><span class="line"> </span><br><span class="line"> <span class="keyword">return</span> <span class="number">0</span>;</span><br><span class="line">}</span><br></pre></td></tr></table></figure>]]></content>
<summary type="html"><h2 id="题目-184">题目</h2>
<p>给定一个正整数 <code>n</code>，我们希望你可以通过一系列的操作，将其变为另一个正整数 <code>m</code>。<br>
操作共分两种：</p>
<ol>
<li>将当前的数乘以 <code>2</code></summary>
<category term="算法" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/"/>
<category term="Acwing" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/Acwing/"/>
<category term="Acwing周赛" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/Acwing/Acwing%E5%91%A8%E8%B5%9B/"/>
</entry>
<entry>
<title>4299-删点</title>
<link href="http://example.com/2022/07/16/algorithm/Acwing/WeeklyMatches/WeeklyMatches38/4299-%E5%88%A0%E7%82%B9/"/>
<id>http://example.com/2022/07/16/algorithm/Acwing/WeeklyMatches/WeeklyMatches38/4299-%E5%88%A0%E7%82%B9/</id>
<published>2022-07-16T03:25:18.925Z</published>
<updated>2022-07-16T12:26:15.608Z</updated>
<content type="html"><![CDATA[<h2 id="题目-183">题目</h2><p>在一个二维平面上有 <code>n</code> 个点，其中没有任何一个点位于 <code>y</code> 轴上。</p><p>请你判断这些点中是否存在一点满足，删除该点后，剩余的所有点都在 y 轴的同一侧。</p><h2 id="输入格式-172">输入格式</h2><p>第一行包含整数 n。</p><p>接下来 n 行，每行包含两个整数 <code>x,y</code>，表示其中一个点的横纵坐标。</p><p>点的位置两两不重合。</p><h2 id="输出格式-172">输出格式</h2><p>如果存在满足要求的点，则输出 <code>Yes</code>，否则输出 <code>No</code>。</p><h2 id="数据范围-198">数据范围</h2><p>前三个测试点满足 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mn>2</mn><mo>≤</mo><mi>n</mi><mo>≤</mo><mn>10</mn></mrow><annotation encoding="application/x-tex">2≤n≤10</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.7804em;vertical-align:-0.136em;"></span><span class="mord">2</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.7719em;vertical-align:-0.136em;"></span><span class="mord mathnormal">n</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.6444em;"></span><span class="mord">10</span></span></span></span>。<br>所有测试点满足 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mn>2</mn><mo>≤</mo><mi>n</mi><mo>≤</mo><mn>100</mn><mtext>，</mtext><mi mathvariant="normal">∣</mi><mi>x</mi><mi mathvariant="normal">∣</mi><mo separator="true">,</mo><mi mathvariant="normal">∣</mi><mi>y</mi><mi mathvariant="normal">∣</mi><mo>≤</mo><mn>100</mn><mtext>，</mtext><mi mathvariant="normal">∣</mi><mi>x</mi><mi mathvariant="normal">∣</mi><mo mathvariant="normal">≠</mo><mn>0</mn></mrow><annotation encoding="application/x-tex">2≤n≤100，|x|,|y|≤100，|x|≠0</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.7804em;vertical-align:-0.136em;"></span><span class="mord">2</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.7719em;vertical-align:-0.136em;"></span><span class="mord mathnormal">n</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:1em;vertical-align:-0.25em;"></span><span class="mord">100</span><span class="mord cjk_fallback">，</span><span class="mord">∣</span><span class="mord mathnormal">x</span><span class="mord">∣</span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord">∣</span><span class="mord mathnormal" style="margin-right:0.03588em;">y</span><span class="mord">∣</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:1em;vertical-align:-0.25em;"></span><span class="mord">100</span><span class="mord cjk_fallback">，</span><span class="mord">∣</span><span class="mord mathnormal">x</span><span class="mord">∣</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel"><span class="mrel"><span class="mord vbox"><span class="thinbox"><span class="rlap"><span class="strut" style="height:0.8889em;vertical-align:-0.1944em;"></span><span class="inner"><span class="mord"><span class="mrel"></span></span></span><span class="fix"></span></span></span></span></span><span class="mrel">=</span></span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.6444em;"></span><span class="mord">0</span></span></span></span>。</p><h2 id="样例-140">样例</h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br><span class="line">24</span><br></pre></td><td class="code"><pre><span class="line">输入样例<span class="number">1</span>：</span><br><span class="line"><span class="number">3</span></span><br><span class="line"><span class="number">1</span> <span class="number">1</span></span><br><span class="line"><span class="number">-1</span> <span class="number">-1</span></span><br><span class="line"><span class="number">2</span> <span class="number">-1</span></span><br><span class="line">输出样例<span class="number">1</span>：</span><br><span class="line">Yes</span><br><span class="line"></span><br><span class="line">输入样例<span class="number">2</span>：</span><br><span class="line"><span class="number">4</span></span><br><span class="line"><span class="number">1</span> <span class="number">1</span></span><br><span class="line"><span class="number">2</span> <span class="number">2</span></span><br><span class="line"><span class="number">-1</span> <span class="number">1</span></span><br><span class="line"><span class="number">-2</span> <span class="number">2</span></span><br><span class="line">输出样例<span class="number">2</span>：</span><br><span class="line">No</span><br><span class="line"></span><br><span class="line">输入样例<span class="number">3</span>：</span><br><span class="line"><span class="number">3</span></span><br><span class="line"><span class="number">1</span> <span class="number">2</span></span><br><span class="line"><span class="number">2</span> <span class="number">1</span></span><br><span class="line"><span class="number">4</span> <span class="number">60</span></span><br><span class="line">输出样例<span class="number">3</span>：</span><br><span class="line">Yes</span><br></pre></td></tr></table></figure><h2 id="分析-149">分析</h2><p>暴力判断<span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>O</mi><mo stretchy="false">(</mo><mi>n</mi><mo stretchy="false">)</mo></mrow><annotation encoding="application/x-tex">O(n)</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:1em;vertical-align:-0.25em;"></span><span class="mord mathnormal" style="margin-right:0.02778em;">O</span><span class="mopen">(</span><span class="mord mathnormal">n</span><span class="mclose">)</span></span></span></span></p><h2 id="解答-201">解答</h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br><span class="line">24</span><br><span class="line">25</span><br><span class="line">26</span><br></pre></td><td class="code"><pre><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><iostream></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><cstring></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><algorithm></span></span></span><br><span class="line"></span><br><span class="line"><span class="keyword">using</span> <span class="keyword">namespace</span> std;</span><br><span class="line"></span><br><span class="line"><span class="function"><span class="type">int</span> <span class="title">main</span><span class="params">()</span></span></span><br><span class="line"><span class="function"></span>{</span><br><span class="line"> <span class="type">int</span> n;</span><br><span class="line"> cin>>n;</span><br><span class="line"> </span><br><span class="line"> <span class="type">int</span> x1=<span class="number">0</span>,x2=<span class="number">0</span>;</span><br><span class="line"> <span class="keyword">for</span> (<span class="type">int</span> i = <span class="number">0</span>; i < n; i ++ )</span><br><span class="line"> {</span><br><span class="line"> <span class="type">int</span> x,y;</span><br><span class="line"> cin>>x>>y;</span><br><span class="line"> </span><br><span class="line"> <span class="keyword">if</span>(x<<span class="number">0</span>) x1++;</span><br><span class="line"> <span class="keyword">else</span> <span class="keyword">if</span>(x><span class="number">0</span>) x2++;</span><br><span class="line"> }</span><br><span class="line"> </span><br><span class="line"> <span class="keyword">if</span>(x1<=<span class="number">1</span>||x2<=<span class="number">1</span>) <span class="built_in">puts</span>(<span class="string">"Yes"</span>);</span><br><span class="line"> <span class="keyword">else</span> <span class="built_in">puts</span>(<span class="string">"No"</span>);</span><br><span class="line"> </span><br><span class="line"> <span class="keyword">return</span> <span class="number">0</span>;</span><br><span class="line">}</span><br></pre></td></tr></table></figure>]]></content>
<summary type="html"><h2 id="题目-183">题目</h2>
<p>在一个二维平面上有 <code>n</code> 个点，其中没有任何一个点位于 <code>y</code> 轴上。</p>
<p>请你判断这些点中是否存在一点满足，删除该点后，剩余的所有点都在 y 轴的同一侧。</p>
<h</summary>
<category term="算法" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/"/>
<category term="Acwing" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/Acwing/"/>
<category term="Acwing周赛" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/Acwing/Acwing%E5%91%A8%E8%B5%9B/"/>
</entry>
<entry>
<title>4298-搭档</title>
<link href="http://example.com/2022/07/16/algorithm/Acwing/WeeklyMatches/WeeklyMatches37/4298-%E6%90%AD%E6%A1%A3/"/>
<id>http://example.com/2022/07/16/algorithm/Acwing/WeeklyMatches/WeeklyMatches37/4298-%E6%90%AD%E6%A1%A3/</id>
<published>2022-07-16T03:25:18.918Z</published>
<updated>2022-07-16T12:26:15.608Z</updated>
<content type="html"><![CDATA[<h2 id="题目-180">题目</h2><p>有 n 个男孩，每个人的魅力值依次为 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><msub><mi>a</mi><mn>1</mn></msub><mo separator="true">,</mo><msub><mi>a</mi><mn>2</mn></msub><mo separator="true">,</mo><mo>…</mo><mo separator="true">,</mo><msub><mi>a</mi><mi>n</mi></msub></mrow><annotation encoding="application/x-tex">a_1,a_2,…,a_n</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.625em;vertical-align:-0.1944em;"></span><span class="mord"><span class="mord mathnormal">a</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3011em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">1</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord mathnormal">a</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3011em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">2</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="minner">…</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord mathnormal">a</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.1514em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">n</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span></span></span></span>.</p><p>有 m 个女孩，每个人的魅力值依次为 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><msub><mi>b</mi><mn>1</mn></msub><mo separator="true">,</mo><msub><mi>b</mi><mn>2</mn></msub><mo separator="true">,</mo><mo>…</mo><mo separator="true">,</mo><msub><mi>b</mi><mi>m</mi></msub></mrow><annotation encoding="application/x-tex">b_1,b_2,…,b_m</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.8889em;vertical-align:-0.1944em;"></span><span class="mord"><span class="mord mathnormal">b</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3011em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">1</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord mathnormal">b</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3011em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">2</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="minner">…</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord mathnormal">b</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.1514em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">m</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span></span></span></span>。</p><p>学校举办舞会，希望选出尽可能多的男女搭档参加。</p><p>已知，当一对男女的魅力值相差不超过 1 时，他们才会愿意组成搭档。</p><p>请问，最多可以同时凑出多少对搭档参加舞会。</p><p>注意：</p><ul><li>不能男男配对或女女配对。</li><li>每个男生最多只能和一个女生配对，反之亦然。</li></ul><h2 id="输入格式-169">输入格式</h2><p>第一行包含整数 n。</p><p>第二行包含 n 个整数 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><msub><mi>a</mi><mn>1</mn></msub><mo separator="true">,</mo><msub><mi>a</mi><mn>2</mn></msub><mo separator="true">,</mo><mo>…</mo><mo separator="true">,</mo><msub><mi>a</mi><mi>n</mi></msub></mrow><annotation encoding="application/x-tex">a_1,a_2,…,a_n</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.625em;vertical-align:-0.1944em;"></span><span class="mord"><span class="mord mathnormal">a</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3011em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">1</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord mathnormal">a</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3011em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">2</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="minner">…</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord mathnormal">a</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.1514em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">n</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span></span></span></span>。</p><p>第三行包含整数 m。</p><p>第四行包含 m 个整数 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><msub><mi>b</mi><mn>1</mn></msub><mo separator="true">,</mo><msub><mi>b</mi><mn>2</mn></msub><mo separator="true">,</mo><mo>…</mo><mo separator="true">,</mo><msub><mi>b</mi><mi>m</mi></msub></mrow><annotation encoding="application/x-tex">b_1,b_2,…,b_m</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.8889em;vertical-align:-0.1944em;"></span><span class="mord"><span class="mord mathnormal">b</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3011em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">1</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord mathnormal">b</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3011em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">2</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="minner">…</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord mathnormal">b</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.1514em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">m</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span></span></span></span>。</p><h2 id="输出格式-169">输出格式</h2><p>一个整数，表示最大可能对数。</p><h2 id="数据范围-195">数据范围</h2><p>前 6 个测试点满足 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mn>1</mn><mo>≤</mo><mi>n</mi><mo separator="true">,</mo><mi>m</mi><mo>≤</mo><mn>5</mn></mrow><annotation encoding="application/x-tex">1≤n,m≤5</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.7804em;vertical-align:-0.136em;"></span><span class="mord">1</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.8304em;vertical-align:-0.1944em;"></span><span class="mord mathnormal">n</span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord mathnormal">m</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.6444em;"></span><span class="mord">5</span></span></span></span>,<br>所有测试点满足 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mn>1</mn><mo>≤</mo><mi>n</mi><mo separator="true">,</mo><mi>m</mi><mo>≤</mo><mn>100</mn><mtext>，</mtext><mn>1</mn><mo>≤</mo><msub><mi>a</mi><mi>i</mi></msub><mo separator="true">,</mo><msub><mi>b</mi><mi>i</mi></msub><mo>≤</mo><mn>100</mn></mrow><annotation encoding="application/x-tex">1≤n,m≤100，1≤a_i,b_i≤100</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.7804em;vertical-align:-0.136em;"></span><span class="mord">1</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.8304em;vertical-align:-0.1944em;"></span><span class="mord mathnormal">n</span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord mathnormal">m</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.8193em;vertical-align:-0.136em;"></span><span class="mord">100</span><span class="mord cjk_fallback">，</span><span class="mord">1</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.8889em;vertical-align:-0.1944em;"></span><span class="mord"><span class="mord mathnormal">a</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">i</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord mathnormal">b</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">i</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.6444em;"></span><span class="mord">100</span></span></span></span>。</p><h2 id="样例-137">样例</h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br><span class="line">24</span><br><span class="line">25</span><br><span class="line">26</span><br></pre></td><td class="code"><pre><span class="line">输入样例<span class="number">1</span>：</span><br><span class="line"><span class="number">4</span></span><br><span class="line"><span class="number">1</span> <span class="number">4</span> <span class="number">6</span> <span class="number">2</span></span><br><span class="line"><span class="number">5</span></span><br><span class="line"><span class="number">5</span> <span class="number">1</span> <span class="number">5</span> <span class="number">7</span> <span class="number">9</span></span><br><span class="line"></span><br><span class="line">输出样例<span class="number">1</span>：</span><br><span class="line"><span class="number">3</span></span><br><span class="line"></span><br><span class="line">输入样例<span class="number">2</span>：</span><br><span class="line"><span class="number">4</span></span><br><span class="line"><span class="number">1</span> <span class="number">2</span> <span class="number">3</span> <span class="number">4</span></span><br><span class="line"><span class="number">4</span></span><br><span class="line"><span class="number">10</span> <span class="number">11</span> <span class="number">12</span> <span class="number">13</span></span><br><span class="line"></span><br><span class="line">输出样例<span class="number">2</span>：</span><br><span class="line"><span class="number">0</span></span><br><span class="line"></span><br><span class="line">输入样例<span class="number">3</span>：</span><br><span class="line"><span class="number">5</span></span><br><span class="line"><span class="number">1</span> <span class="number">1</span> <span class="number">1</span> <span class="number">1</span> <span class="number">1</span></span><br><span class="line"><span class="number">3</span></span><br><span class="line"><span class="number">1</span> <span class="number">2</span> <span class="number">3</span></span><br><span class="line"></span><br><span class="line">输出样例<span class="number">3</span>：</span><br><span class="line"><span class="number">2</span></span><br></pre></td></tr></table></figure><h2 id="分析-146">分析</h2><ol><li>典型的匈牙利算法(二部图的最大匹配)</li><li>如何抽象出来:<br>(1). 男生作为二部图的左半部,女生作为右半部,男生和女生的编号作为图的点<br>(2). <code>当一对男女的魅力值相差不超过 1 时，他们才会愿意组成搭档</code>满足这个条件才能<code>add</code>一个边。</li><li>算法流程:<br>(1). 男生点和他的邻接点进行判断，看能不能有效匹配上<br>(2). 有效匹配的条件是:必须他的邻接点没有全部已经被匹配或者已经匹配了的女生所匹配的男生还有备胎，能让这个女生退出之前的匹配，然后和自己匹配<br>(3). 比如:现在男生A能和女生a匹配或者A想要和a匹配，但是a已经和男生B匹配了，可是B还有一个备胎女生b，A就求B和b匹配，自己就可以和a匹配了。</li></ol><h2 id="解答-198">解答</h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br><span class="line">24</span><br><span class="line">25</span><br><span class="line">26</span><br><span class="line">27</span><br><span class="line">28</span><br><span class="line">29</span><br><span class="line">30</span><br><span class="line">31</span><br><span class="line">32</span><br><span class="line">33</span><br><span class="line">34</span><br><span class="line">35</span><br><span class="line">36</span><br><span class="line">37</span><br><span class="line">38</span><br><span class="line">39</span><br><span class="line">40</span><br><span class="line">41</span><br><span class="line">42</span><br><span class="line">43</span><br><span class="line">44</span><br><span class="line">45</span><br><span class="line">46</span><br><span class="line">47</span><br><span class="line">48</span><br><span class="line">49</span><br><span class="line">50</span><br><span class="line">51</span><br><span class="line">52</span><br><span class="line">53</span><br><span class="line">54</span><br><span class="line">55</span><br><span class="line">56</span><br><span class="line">57</span><br></pre></td><td class="code"><pre><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><iostream></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><cstring></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><algorithm></span></span></span><br><span class="line"></span><br><span class="line"><span class="keyword">using</span> <span class="keyword">namespace</span> std;</span><br><span class="line"></span><br><span class="line"><span class="type">const</span> <span class="type">int</span> N = <span class="number">110</span>,M=<span class="number">10010</span>;<span class="comment">//注意数据,如果每个男生都可以和女生尝试匹配的话,那么边就可能有N*N个(N个点)</span></span><br><span class="line"></span><br><span class="line"><span class="type">int</span> a[N],b[N];</span><br><span class="line"><span class="type">int</span> e[M],ne[M],h[N],idx;</span><br><span class="line"><span class="type">bool</span> st[N];</span><br><span class="line"><span class="type">int</span> match[N];</span><br><span class="line"></span><br><span class="line"><span class="type">int</span> n1,n2;</span><br><span class="line"></span><br><span class="line"><span class="function"><span class="type">void</span> <span class="title">add</span><span class="params">(<span class="type">int</span> a, <span class="type">int</span> b)</span> <span class="comment">// 添加一条边a->b</span></span></span><br><span class="line"><span class="function"></span>{</span><br><span class="line"> e[idx] = b, ne[idx] = h[a], h[a] = idx ++ ;</span><br><span class="line">}</span><br><span class="line"></span><br><span class="line"><span class="function"><span class="type">bool</span> <span class="title">find</span><span class="params">(<span class="type">int</span> u)</span></span>{</span><br><span class="line"> <span class="keyword">for</span> (<span class="type">int</span> i = h[u]; i != <span class="number">-1</span>; i = ne[i] ){</span><br><span class="line"> <span class="type">int</span> j=e[i];</span><br><span class="line"> <span class="keyword">if</span>(!st[j]){</span><br><span class="line"> st[j]=<span class="literal">true</span>;</span><br><span class="line"> <span class="keyword">if</span>(match[j]==<span class="number">0</span>||<span class="built_in">find</span>(match[j])){</span><br><span class="line"> match[j]=u;</span><br><span class="line"> <span class="keyword">return</span> <span class="literal">true</span>;</span><br><span class="line"> }</span><br><span class="line"> }</span><br><span class="line"> }</span><br><span class="line"> <span class="keyword">return</span> <span class="literal">false</span>;</span><br><span class="line">}</span><br><span class="line"></span><br><span class="line"><span class="function"><span class="type">int</span> <span class="title">main</span><span class="params">()</span></span></span><br><span class="line"><span class="function"></span>{</span><br><span class="line"> <span class="built_in">memset</span>(h, <span class="number">-1</span>, <span class="keyword">sizeof</span> h);</span><br><span class="line"> </span><br><span class="line"> <span class="built_in">scanf</span>(<span class="string">"%d"</span>, &n1);</span><br><span class="line"> <span class="keyword">for</span> (<span class="type">int</span> i = <span class="number">1</span>; i <= n1; i ++ ) <span class="built_in">scanf</span>(<span class="string">"%d"</span>, &a[i]);</span><br><span class="line"> </span><br><span class="line"> <span class="built_in">scanf</span>(<span class="string">"%d"</span>, &n2);</span><br><span class="line"> <span class="keyword">for</span> (<span class="type">int</span> i = <span class="number">1</span>; i <= n2; i ++ ) <span class="built_in">scanf</span>(<span class="string">"%d"</span>, &b[i]);</span><br><span class="line"> </span><br><span class="line"> <span class="keyword">for</span> (<span class="type">int</span> i = <span class="number">1</span>; i <= n1; i ++ )</span><br><span class="line"> <span class="keyword">for</span> (<span class="type">int</span> j = <span class="number">1</span>; j <= n2; j ++ )</span><br><span class="line"> <span class="keyword">if</span>(<span class="built_in">abs</span>(a[i]-b[j])<=<span class="number">1</span>)</span><br><span class="line"> <span class="built_in">add</span>(i, j);</span><br><span class="line"> </span><br><span class="line"> <span class="type">int</span> ans; </span><br><span class="line"> <span class="keyword">for</span> (<span class="type">int</span> i = <span class="number">1</span>; i <= n1; i ++ ){</span><br><span class="line"> <span class="built_in">memset</span>(st, <span class="number">0</span>, <span class="keyword">sizeof</span> st);</span><br><span class="line"> <span class="keyword">if</span>(<span class="built_in">find</span>(i)) ans++;</span><br><span class="line"> }</span><br><span class="line"> <span class="built_in">printf</span>(<span class="string">"%d"</span>,ans);</span><br><span class="line"> <span class="keyword">return</span> <span class="number">0</span>;</span><br><span class="line">}</span><br></pre></td></tr></table></figure>]]></content>
<summary type="html"><h2 id="题目-180">题目</h2>
<p>有 n 个男孩，每个人的魅力值依次为 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML</summary>
<category term="算法" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/"/>
<category term="Acwing" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/Acwing/"/>
<category term="Acwing周赛" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/Acwing/Acwing%E5%91%A8%E8%B5%9B/"/>
</entry>
<entry>
<title>4297-截断数组</title>
<link href="http://example.com/2022/07/16/algorithm/Acwing/WeeklyMatches/WeeklyMatches37/4297-%E6%88%AA%E6%96%AD%E6%95%B0%E7%BB%84/"/>
<id>http://example.com/2022/07/16/algorithm/Acwing/WeeklyMatches/WeeklyMatches37/4297-%E6%88%AA%E6%96%AD%E6%95%B0%E7%BB%84/</id>
<published>2022-07-16T03:25:18.915Z</published>
<updated>2022-07-16T12:26:15.608Z</updated>
<content type="html"><![CDATA[<h2 id="题目-178">题目</h2><p>给定一个长度为 <code>n</code> 的数组 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><msub><mi>d</mi><mn>1</mn></msub><mo separator="true">,</mo><msub><mi>d</mi><mn>2</mn></msub><mo separator="true">,</mo><mo>…</mo><mo separator="true">,</mo><msub><mi>d</mi><mi>n</mi></msub></mrow><annotation encoding="application/x-tex">d_1,d_2,…,d_n</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.8889em;vertical-align:-0.1944em;"></span><span class="mord"><span class="mord mathnormal">d</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3011em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">1</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord mathnormal">d</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3011em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">2</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="minner">…</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord mathnormal">d</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.1514em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">n</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span></span></span></span>。</p><p>现在，要将该数组从中间截断，得到三个子数组（可以为空）。</p><p>不妨设第一个子数组包含 <code>a</code> 个元素，第二个子数组包含 <code>b</code> 个元素，第三个子数组包含 <code>c</code> 个元素。</p><p>那么三个子数组的各元素之和 <code>sum1</code>,<code>sum2</code>,<code>sum3</code> 依次为：</p><p><span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>s</mi><mi>u</mi><mi>m</mi><mn>1</mn><mo>=</mo><msub><mo>∑</mo><mrow><mn>1</mn><mo>≤</mo><mi>i</mi><mo>≤</mo><mi>a</mi></mrow></msub><msub><mi>d</mi><mi>i</mi></msub><mtext>，</mtext><mi>s</mi><mi>u</mi><mi>m</mi><mn>2</mn><mo>=</mo><msub><mo>∑</mo><mrow><mi>a</mi><mo>+</mo><mn>1</mn><mo>≤</mo><mi>i</mi><mo>≤</mo><mi>a</mi><mo>+</mo><mi>b</mi></mrow></msub><msub><mi>d</mi><mi>i</mi></msub><mtext>，</mtext><mi>s</mi><mi>u</mi><mi>m</mi><mn>3</mn><mo>=</mo><msub><mo>∑</mo><mrow><mi>a</mi><mo>+</mo><mi>b</mi><mo>+</mo><mn>1</mn><mo>≤</mo><mi>i</mi><mo>≤</mo><mi>a</mi><mo>+</mo><mi>b</mi><mo>+</mo><mi>c</mi></mrow></msub><msub><mi>d</mi><mi>i</mi></msub><mtext>。</mtext></mrow><annotation encoding="application/x-tex">sum1=\sum_{1≤i≤a}{d_i}，sum2=\sum_{a+1≤i≤a+b}d_i，sum3=\sum_{a+b+1≤i≤a+b+c}d_i。</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.6444em;"></span><span class="mord mathnormal">s</span><span class="mord mathnormal">u</span><span class="mord mathnormal">m</span><span class="mord">1</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">=</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:1.1449em;vertical-align:-0.3949em;"></span><span class="mop"><span class="mop op-symbol small-op" style="position:relative;top:0em;">∑</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.162em;"><span style="top:-2.4003em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight"><span class="mord mtight">1</span><span class="mrel mtight">≤</span><span class="mord mathnormal mtight">i</span><span class="mrel mtight">≤</span><span class="mord mathnormal mtight">a</span></span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.3949em;"><span></span></span></span></span></span></span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord"><span class="mord mathnormal">d</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">i</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span></span><span class="mord cjk_fallback">，</span><span class="mord mathnormal">s</span><span class="mord mathnormal">u</span><span class="mord mathnormal">m</span><span class="mord">2</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">=</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:1.1449em;vertical-align:-0.3949em;"></span><span class="mop"><span class="mop op-symbol small-op" style="position:relative;top:0em;">∑</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.1864em;"><span style="top:-2.4003em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight"><span class="mord mathnormal mtight">a</span><span class="mbin mtight">+</span><span class="mord mtight">1</span><span class="mrel mtight">≤</span><span class="mord mathnormal mtight">i</span><span class="mrel mtight">≤</span><span class="mord mathnormal mtight">a</span><span class="mbin mtight">+</span><span class="mord mathnormal mtight">b</span></span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.3949em;"><span></span></span></span></span></span></span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord mathnormal">d</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">i</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mord cjk_fallback">，</span><span class="mord mathnormal">s</span><span class="mord mathnormal">u</span><span class="mord mathnormal">m</span><span class="mord">3</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">=</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:1.1449em;vertical-align:-0.3949em;"></span><span class="mop"><span class="mop op-symbol small-op" style="position:relative;top:0em;">∑</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.1864em;"><span style="top:-2.4003em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight"><span class="mord mathnormal mtight">a</span><span class="mbin mtight">+</span><span class="mord mathnormal mtight">b</span><span class="mbin mtight">+</span><span class="mord mtight">1</span><span class="mrel mtight">≤</span><span class="mord mathnormal mtight">i</span><span class="mrel mtight">≤</span><span class="mord mathnormal mtight">a</span><span class="mbin mtight">+</span><span class="mord mathnormal mtight">b</span><span class="mbin mtight">+</span><span class="mord mathnormal mtight">c</span></span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.3949em;"><span></span></span></span></span></span></span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord mathnormal">d</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">i</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mord cjk_fallback">。</span></span></span></span></p><p>注意，空数组的各元素之和为 0。</p><p>我们希望截断后的三个子数组满足：</p><ul><li>sum1=sum3。</li><li>满足上一条件的情况下，sum1 尽可能大。<br>请你计算并输出 sum1 的最大可能值。</li></ul><p>显然，本题一定有解，因为可以令 <code>a=0,b=n,c=0</code>。</p><h2 id="输入格式-167">输入格式</h2><p>第一行包含整数 n。</p><p>第二行包含 n 个整数 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><msub><mi>d</mi><mn>1</mn></msub><mo separator="true">,</mo><msub><mi>d</mi><mn>2</mn></msub><mo separator="true">,</mo><mo>…</mo><mo separator="true">,</mo><msub><mi>d</mi><mi>n</mi></msub></mrow><annotation encoding="application/x-tex">d_1,d_2,…,d_n</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.8889em;vertical-align:-0.1944em;"></span><span class="mord"><span class="mord mathnormal">d</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3011em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">1</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord mathnormal">d</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3011em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">2</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="minner">…</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord mathnormal">d</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.1514em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">n</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span></span></span></span>。</p><h2 id="输出格式-167">输出格式</h2><p>输出一个整数，表示 sum1 的最大可能值。</p><h2 id="数据范围-193">数据范围</h2><p>前 6 个测试点满足 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mn>1</mn><mo>≤</mo><mi>n</mi><mo>≤</mo><mn>10</mn></mrow><annotation encoding="application/x-tex">1≤n≤10</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.7804em;vertical-align:-0.136em;"></span><span class="mord">1</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.7719em;vertical-align:-0.136em;"></span><span class="mord mathnormal">n</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.6444em;"></span><span class="mord">10</span></span></span></span>。<br>所有测试点满足 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mn>1</mn><mo>≤</mo><mi>n</mi><mo>≤</mo><mn>2</mn><mo>×</mo><mn>1</mn><msup><mn>0</mn><mn>5</mn></msup><mtext>，</mtext><mn>1</mn><mo>≤</mo><msub><mi>d</mi><mi>i</mi></msub><mo>≤</mo><mn>1</mn><msup><mn>0</mn><mn>9</mn></msup></mrow><annotation encoding="application/x-tex">1≤n≤2×10^5，1≤d_i≤10^9</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.7804em;vertical-align:-0.136em;"></span><span class="mord">1</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.7719em;vertical-align:-0.136em;"></span><span class="mord mathnormal">n</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.7278em;vertical-align:-0.0833em;"></span><span class="mord">2</span><span class="mspace" style="margin-right:0.2222em;"></span><span class="mbin">×</span><span class="mspace" style="margin-right:0.2222em;"></span></span><span class="base"><span class="strut" style="height:0.9501em;vertical-align:-0.136em;"></span><span class="mord">1</span><span class="mord"><span class="mord">0</span><span class="msupsub"><span class="vlist-t"><span class="vlist-r"><span class="vlist" style="height:0.8141em;"><span style="top:-3.063em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">5</span></span></span></span></span></span></span></span><span class="mord cjk_fallback">，</span><span class="mord">1</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.8444em;vertical-align:-0.15em;"></span><span class="mord"><span class="mord mathnormal">d</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">i</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.8141em;"></span><span class="mord">1</span><span class="mord"><span class="mord">0</span><span class="msupsub"><span class="vlist-t"><span class="vlist-r"><span class="vlist" style="height:0.8141em;"><span style="top:-3.063em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">9</span></span></span></span></span></span></span></span></span></span></span>。</p><h2 id="样例-135">样例</h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br></pre></td><td class="code"><pre><span class="line">输入样例<span class="number">1</span>：</span><br><span class="line"><span class="number">5</span></span><br><span class="line"><span class="number">1</span> <span class="number">3</span> <span class="number">1</span> <span class="number">1</span> <span class="number">4</span></span><br><span class="line"></span><br><span class="line">输出样例<span class="number">1</span>：</span><br><span class="line"><span class="number">5</span></span><br><span class="line"></span><br><span class="line">输入样例<span class="number">2</span>：</span><br><span class="line"><span class="number">5</span></span><br><span class="line"><span class="number">1</span> <span class="number">3</span> <span class="number">2</span> <span class="number">1</span> <span class="number">4</span></span><br><span class="line"></span><br><span class="line">输出样例<span class="number">2</span>：</span><br><span class="line"><span class="number">4</span></span><br><span class="line"></span><br><span class="line">输入样例<span class="number">3</span>：</span><br><span class="line"><span class="number">3</span></span><br><span class="line"><span class="number">4</span> <span class="number">1</span> <span class="number">2</span></span><br><span class="line"></span><br><span class="line">输出样例<span class="number">3</span>：</span><br><span class="line"><span class="number">0</span></span><br></pre></td></tr></table></figure><h2 id="分析-144">分析</h2><ol><li>sum1其实就是数组前a个数的和，sum3就是数组后c个数的和，那么我们就可以想到把前缀和先算好，再来进一步的比较。</li><li>由于sum可能达到<span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mn>1</mn><mo>×</mo><mn>1</mn><msup><mn>0</mn><mn>14</mn></msup></mrow><annotation encoding="application/x-tex">1×10^{14}</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.7278em;vertical-align:-0.0833em;"></span><span class="mord">1</span><span class="mspace" style="margin-right:0.2222em;"></span><span class="mbin">×</span><span class="mspace" style="margin-right:0.2222em;"></span></span><span class="base"><span class="strut" style="height:0.8141em;"></span><span class="mord">1</span><span class="mord"><span class="mord">0</span><span class="msupsub"><span class="vlist-t"><span class="vlist-r"><span class="vlist" style="height:0.8141em;"><span style="top:-3.063em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight"><span class="mord mtight">14</span></span></span></span></span></span></span></span></span></span></span></span>，所以考虑用<code>unsigned long long</code>来储存。</li><li>接下来就要查找前缀和了，可以考虑使用双指针,l和r,由于数组中都是非负整数，所以当集合内元素增加时，sum是非严格单调递增的。所以当sum1<code><</code>sum2的时候,就需要增加左边元素个数，sum1>sum2的时候就需要增加右边元素个数，直到sum1=sum2就更新sum1的最大值,直致<code>l!<r</code>。</li></ol><h2 id="解答-196">解答</h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br><span class="line">24</span><br><span class="line">25</span><br><span class="line">26</span><br><span class="line">27</span><br><span class="line">28</span><br><span class="line">29</span><br><span class="line">30</span><br><span class="line">31</span><br><span class="line">32</span><br><span class="line">33</span><br><span class="line">34</span><br><span class="line">35</span><br><span class="line">36</span><br><span class="line">37</span><br><span class="line">38</span><br><span class="line">39</span><br><span class="line">40</span><br><span class="line">41</span><br><span class="line">42</span><br><span class="line">43</span><br></pre></td><td class="code"><pre><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><iostream></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><cstring></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><algorithm></span></span></span><br><span class="line"></span><br><span class="line"><span class="keyword">using</span> <span class="keyword">namespace</span> std;</span><br><span class="line"></span><br><span class="line"><span class="keyword">typedef</span> <span class="type">unsigned</span> <span class="type">long</span> <span class="type">long</span> ULL;</span><br><span class="line"></span><br><span class="line"><span class="type">const</span> <span class="type">int</span> N = <span class="number">2e5</span>+<span class="number">10</span>;</span><br><span class="line"></span><br><span class="line">ULL s[N],d[N];</span><br><span class="line"></span><br><span class="line"><span class="type">int</span> n;</span><br><span class="line"></span><br><span class="line"><span class="function"><span class="type">int</span> <span class="title">main</span><span class="params">()</span></span></span><br><span class="line"><span class="function"></span>{</span><br><span class="line"> <span class="built_in">scanf</span>(<span class="string">"%d"</span>, &n);</span><br><span class="line"> </span><br><span class="line"> <span class="keyword">for</span> (<span class="type">int</span> i = <span class="number">1</span>; i <= n; i ++ )</span><br><span class="line"> <span class="built_in">scanf</span>(<span class="string">"%lld"</span>, &d[i]);</span><br><span class="line"> </span><br><span class="line"> <span class="keyword">for</span> (<span class="type">int</span> i = <span class="number">1</span>; i <= n; i ++ )</span><br><span class="line"> s[i]=d[i]+s[i<span class="number">-1</span>];</span><br><span class="line"> </span><br><span class="line"> <span class="type">int</span> l=<span class="number">1</span>,r=n+<span class="number">1</span>;</span><br><span class="line"> ULL ans=<span class="number">0</span>;</span><br><span class="line"> <span class="keyword">while</span>(l<r){</span><br><span class="line"> ULL sum1=s[l]-s[<span class="number">0</span>],sum3=s[n]-s[r<span class="number">-1</span>];</span><br><span class="line"> <span class="keyword">if</span>(sum1==sum3){</span><br><span class="line"> ans=<span class="built_in">max</span>(ans,sum1);</span><br><span class="line"> r--;</span><br><span class="line"> }<span class="keyword">else</span> <span class="keyword">if</span>(sum1>sum3){</span><br><span class="line"> r--;</span><br><span class="line"> }<span class="keyword">else</span> <span class="keyword">if</span>(sum1<sum3){</span><br><span class="line"> l++;</span><br><span class="line"> }</span><br><span class="line"> }</span><br><span class="line"> </span><br><span class="line"> <span class="built_in">printf</span>(<span class="string">"%lld"</span>,ans);</span><br><span class="line"> </span><br><span class="line"> <span class="keyword">return</span> <span class="number">0</span>;</span><br><span class="line"> </span><br><span class="line">}</span><br></pre></td></tr></table></figure>]]></content>
<summary type="html"><h2 id="题目-178">题目</h2>
<p>给定一个长度为 <code>n</code> 的数组 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Mat</summary>
<category term="算法" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/"/>
<category term="Acwing" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/Acwing/"/>
<category term="Acwing周赛" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/Acwing/Acwing%E5%91%A8%E8%B5%9B/"/>
</entry>
<entry>
<title>4296-合适数对</title>
<link href="http://example.com/2022/07/16/algorithm/Acwing/WeeklyMatches/WeeklyMatches37/4296-%E5%90%88%E9%80%82%E6%95%B0%E5%AF%B9/"/>
<id>http://example.com/2022/07/16/algorithm/Acwing/WeeklyMatches/WeeklyMatches37/4296-%E5%90%88%E9%80%82%E6%95%B0%E5%AF%B9/</id>
<published>2022-07-16T03:25:18.913Z</published>
<updated>2022-07-16T12:26:15.608Z</updated>
<content type="html"><![CDATA[<h2 id="题目-177">题目</h2><p>给定三个正整数 <code>n,a,b</code>，请你找到两个非负整数 <code>x,y</code>，使得 <code>ax+by=n</code> 成立。</p><h2 id="输入格式-166">输入格式</h2><p>第一行包含整数 n。</p><p>第二行包含整数 a。</p><p>第三行包含整数 b。</p><h2 id="输出格式-166">输出格式</h2><p>如果不存在符合条件的 <code>x,y</code>，则输出一行 <code>NO</code> 即可。</p><p>否则，第一行输出 <code>YES</code>，第二行输出 <code>x,y</code>。</p><p>如果方案不唯一，则输出 <code>x</code> 最小的方案。</p><h2 id="数据范围-192">数据范围</h2><p>所有测试点满足 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mn>1</mn><mo>≤</mo><mi>n</mi><mo separator="true">,</mo><mi>a</mi><mo separator="true">,</mo><mi>b</mi><mo>≤</mo><mn>1000</mn></mrow><annotation encoding="application/x-tex">1≤n,a,b≤1000</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.7804em;vertical-align:-0.136em;"></span><span class="mord">1</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.8889em;vertical-align:-0.1944em;"></span><span class="mord mathnormal">n</span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord mathnormal">a</span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord mathnormal">b</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.6444em;"></span><span class="mord">1000</span></span></span></span>。</p><h2 id="样例-134">样例</h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br><span class="line">24</span><br><span class="line">25</span><br></pre></td><td class="code"><pre><span class="line">输入样例<span class="number">1</span>：</span><br><span class="line"><span class="number">7</span></span><br><span class="line"><span class="number">2</span></span><br><span class="line"><span class="number">3</span></span><br><span class="line"></span><br><span class="line">输出样例<span class="number">1</span>：</span><br><span class="line">YES</span><br><span class="line"><span class="number">2</span> <span class="number">1</span></span><br><span class="line"></span><br><span class="line">输入样例<span class="number">2</span>：</span><br><span class="line"><span class="number">100</span></span><br><span class="line"><span class="number">25</span></span><br><span class="line"><span class="number">10</span></span><br><span class="line"></span><br><span class="line">输出样例<span class="number">2</span>：</span><br><span class="line">YES</span><br><span class="line"><span class="number">0</span> <span class="number">10</span></span><br><span class="line"></span><br><span class="line">输入样例<span class="number">3</span>：</span><br><span class="line"><span class="number">15</span></span><br><span class="line"><span class="number">4</span></span><br><span class="line"><span class="number">8</span></span><br><span class="line"></span><br><span class="line">输出样例<span class="number">3</span>：</span><br><span class="line">NO</span><br></pre></td></tr></table></figure><h2 id="分析-143">分析</h2><p>把i从零开始枚举，一直到a*i<=n。然后计算b</p><h2 id="解答-195">解答</h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br></pre></td><td class="code"><pre><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><iostream></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><cstring></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><algorithm></span></span></span><br><span class="line"></span><br><span class="line"><span class="keyword">using</span> <span class="keyword">namespace</span> std;</span><br><span class="line"></span><br><span class="line"><span class="function"><span class="type">int</span> <span class="title">main</span><span class="params">()</span></span></span><br><span class="line"><span class="function"></span>{</span><br><span class="line"> <span class="type">int</span> n,a,b;</span><br><span class="line"> <span class="built_in">scanf</span>(<span class="string">"%d%d%d"</span>, &n, &a,&b);</span><br><span class="line"> <span class="type">bool</span> flag=<span class="literal">false</span>;</span><br><span class="line"> <span class="keyword">for</span> (<span class="type">int</span> i = <span class="number">0</span>; a*i <= n; i ++ ){</span><br><span class="line"> <span class="type">int</span> t=(n-a*i)%b;</span><br><span class="line"> <span class="keyword">if</span>(t==<span class="number">0</span>){</span><br><span class="line"> <span class="built_in">puts</span>(<span class="string">"YES"</span>);</span><br><span class="line"> <span class="built_in">printf</span>(<span class="string">"%d %d"</span>,i,(n-a*i)/b);</span><br><span class="line"> flag=<span class="literal">true</span>;</span><br><span class="line"> <span class="keyword">break</span>;</span><br><span class="line"> }</span><br><span class="line"> }</span><br><span class="line"> <span class="keyword">if</span>(!flag) <span class="built_in">printf</span>(<span class="string">"NO"</span>);</span><br><span class="line"> <span class="keyword">return</span> <span class="number">0</span>;</span><br><span class="line">}</span><br></pre></td></tr></table></figure>]]></content>
<summary type="html"><h2 id="题目-177">题目</h2>
<p>给定三个正整数 <code>n,a,b</code>，请你找到两个非负整数 <code>x,y</code>，使得 <code>ax+by=n</code> 成立。</p>
<h2 id="输入格式-166">输入格式</h2</summary>
<category term="算法" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/"/>
<category term="Acwing" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/Acwing/"/>
<category term="Acwing周赛" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/Acwing/Acwing%E5%91%A8%E8%B5%9B/"/>
</entry>
<entry>
<title>4215-处理字符串</title>
<link href="http://example.com/2022/07/16/algorithm/Acwing/WeeklyMatches/WeeklyMatches36/4215_%E5%A4%84%E7%90%86%E5%AD%97%E7%AC%A6%E4%B8%B2/"/>
<id>http://example.com/2022/07/16/algorithm/Acwing/WeeklyMatches/WeeklyMatches36/4215_%E5%A4%84%E7%90%86%E5%AD%97%E7%AC%A6%E4%B8%B2/</id>
<published>2022-07-16T03:25:18.908Z</published>
<updated>2022-07-16T12:26:15.608Z</updated>
<content type="html"><![CDATA[<h2 id="题目-176"><strong>题目</strong></h2><p>给定一个由大小写字母构成的字符串，请你对该字符串进行如下处理：</p><p>将所有大写字母替换为相应的小写字母。<br>删除其中的所有元音字母。<br>在每个辅音字母前面插入一个 .。<br>字母 <code>a，o，y，e，u，i</code> 为元音字母，其余字母均为辅音字母。</p><p>注意，<code>y</code> 其实是半元音字母，在本题中规定其为元音字母。</p><h2 id="输入格式-165"><strong>输入格式</strong></h2><p>一个由大小写字母构成的字符串。</p><h2 id="输出格式-165"><strong>输出格式</strong></h2><p>输出处理后的字符串。</p><p>保证处理后的字符串不为空。</p><h2 id="数据范围-191"><strong>数据范围</strong></h2><p>所有测试点满足，字符串长度范围 <code>[1,100]</code>。</p><h2 id="样例-133"><strong>样例</strong></h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br></pre></td><td class="code"><pre><span class="line">输入样例<span class="number">1</span>：</span><br><span class="line">tour</span><br><span class="line">输出样例<span class="number">1</span>：</span><br><span class="line">.t.r</span><br><span class="line">输入样例<span class="number">2</span>：</span><br><span class="line">aBAcAba</span><br><span class="line">输出样例<span class="number">2</span>：</span><br><span class="line">.b.c.b</span><br></pre></td></tr></table></figure><h2 id="解答-194"><strong>解答</strong></h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br></pre></td><td class="code"><pre><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string">"bits/stdc++.h"</span></span></span><br><span class="line"></span><br><span class="line"><span class="keyword">using</span> <span class="keyword">namespace</span> std;</span><br><span class="line"></span><br><span class="line"><span class="function"><span class="type">int</span> <span class="title">main</span><span class="params">()</span></span></span><br><span class="line"><span class="function"></span>{</span><br><span class="line"> string str;</span><br><span class="line"> cin>>str;</span><br><span class="line"> <span class="type">char</span> u[<span class="number">8</span>]=<span class="string">"aoyeui"</span>;</span><br><span class="line"> <span class="keyword">for</span> (<span class="type">int</span> i = <span class="number">0</span>; i < str.<span class="built_in">size</span>(); i ++ ){</span><br><span class="line"> <span class="keyword">if</span>(str[i]<=<span class="string">'Z'</span>&&str[i]>=<span class="string">'A'</span>) str[i]+=<span class="number">32</span>;</span><br><span class="line"> </span><br><span class="line"> <span class="type">bool</span> flag=<span class="literal">false</span>;</span><br><span class="line"> <span class="keyword">for</span>(<span class="type">int</span> j=<span class="number">0</span>;j<<span class="number">6</span>;j++){</span><br><span class="line"> <span class="keyword">if</span>(str[i]==u[j]){</span><br><span class="line"> flag=<span class="literal">true</span>;</span><br><span class="line"> <span class="keyword">break</span>;</span><br><span class="line"> }</span><br><span class="line"> }</span><br><span class="line"> <span class="keyword">if</span>(!flag) cout<<<span class="string">'.'</span><<str[i];</span><br><span class="line"> }</span><br><span class="line"> <span class="keyword">return</span> <span class="number">0</span>;</span><br><span class="line">}</span><br></pre></td></tr></table></figure>]]></content>
<summary type="html"><h2 id="题目-176"><strong>题目</strong></h2>
<p>给定一个由大小写字母构成的字符串，请你对该字符串进行如下处理：</p>
<p>将所有大写字母替换为相应的小写字母。<br>
删除其中的所有元音字母。<br>
在每个辅音字母前面插入一个 .。<</summary>
<category term="算法" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/"/>
<category term="Acwing" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/Acwing/"/>
<category term="Acwing周赛" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/Acwing/Acwing%E5%91%A8%E8%B5%9B/"/>
</entry>
<entry>
<title>4214-三元组</title>
<link href="http://example.com/2022/07/16/algorithm/Acwing/WeeklyMatches/WeeklyMatches35/4214_%E4%B8%89%E5%85%83%E7%BB%84/"/>
<id>http://example.com/2022/07/16/algorithm/Acwing/WeeklyMatches/WeeklyMatches35/4214_%E4%B8%89%E5%85%83%E7%BB%84/</id>
<published>2022-07-16T03:25:18.903Z</published>
<updated>2022-07-16T12:26:15.608Z</updated>
<content type="html"><![CDATA[<h2 id="题目-174"><strong>题目</strong></h2><p>给定两个长度为 n 的整数序列 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><msub><mi>s</mi><mn>1</mn></msub><mo separator="true">,</mo><msub><mi>s</mi><mn>2</mn></msub><mo separator="true">,</mo><mo>…</mo><mo separator="true">,</mo><msub><mi>s</mi><mi>n</mi></msub><mtext>和</mtext><msub><mi>c</mi><mn>1</mn></msub><mo separator="true">,</mo><msub><mi>c</mi><mn>2</mn></msub><mo separator="true">,</mo><mo>…</mo><mo separator="true">,</mo><msub><mi>c</mi><mi>n</mi></msub></mrow><annotation encoding="application/x-tex">s_1,s_2,…,s_n 和 c_1,c_2,…,c_n</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.8778em;vertical-align:-0.1944em;"></span><span class="mord"><span class="mord mathnormal">s</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3011em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">1</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord mathnormal">s</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3011em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">2</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="minner">…</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord mathnormal">s</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.1514em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">n</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mord cjk_fallback">和</span><span class="mord"><span class="mord mathnormal">c</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3011em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">1</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord mathnormal">c</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3011em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">2</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="minner">…</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord mathnormal">c</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.1514em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">n</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span></span></span></span>。</p><p>请你找到一个三元组 (i,j,k)，满足以下所有条件：</p><ul><li><span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>i</mi><mo><</mo><mi>j</mi><mo><</mo><mi>k</mi></mrow><annotation encoding="application/x-tex">i<j<k</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.6986em;vertical-align:-0.0391em;"></span><span class="mord mathnormal">i</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel"><</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.854em;vertical-align:-0.1944em;"></span><span class="mord mathnormal" style="margin-right:0.05724em;">j</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel"><</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.6944em;"></span><span class="mord mathnormal" style="margin-right:0.03148em;">k</span></span></span></span></li><li><span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><msub><mi>s</mi><mi>i</mi></msub><mo><</mo><msub><mi>s</mi><mi>j</mi></msub><mo><</mo><msub><mi>s</mi><mi>k</mi></msub></mrow><annotation encoding="application/x-tex">s_i<s_j<s_k</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.6891em;vertical-align:-0.15em;"></span><span class="mord"><span class="mord mathnormal">s</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">i</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel"><</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.8252em;vertical-align:-0.2861em;"></span><span class="mord"><span class="mord mathnormal">s</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight" style="margin-right:0.05724em;">j</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.2861em;"><span></span></span></span></span></span></span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel"><</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.5806em;vertical-align:-0.15em;"></span><span class="mord"><span class="mord mathnormal">s</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3361em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight" style="margin-right:0.03148em;">k</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span></span></span></span></li><li><span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><msub><mi>c</mi><mi>i</mi></msub><mo>+</mo><msub><mi>c</mi><mi>j</mi></msub><mo>+</mo><msub><mi>c</mi><mi>k</mi></msub></mrow><annotation encoding="application/x-tex">c_i+c_j+c_k</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.7333em;vertical-align:-0.15em;"></span><span class="mord"><span class="mord mathnormal">c</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">i</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mspace" style="margin-right:0.2222em;"></span><span class="mbin">+</span><span class="mspace" style="margin-right:0.2222em;"></span></span><span class="base"><span class="strut" style="height:0.8694em;vertical-align:-0.2861em;"></span><span class="mord"><span class="mord mathnormal">c</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight" style="margin-right:0.05724em;">j</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.2861em;"><span></span></span></span></span></span></span><span class="mspace" style="margin-right:0.2222em;"></span><span class="mbin">+</span><span class="mspace" style="margin-right:0.2222em;"></span></span><span class="base"><span class="strut" style="height:0.5806em;vertical-align:-0.15em;"></span><span class="mord"><span class="mord mathnormal">c</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3361em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight" style="margin-right:0.03148em;">k</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span></span></span></span> 尽可能小</li></ul><p>输出 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><msub><mi>c</mi><mi>i</mi></msub><mo>+</mo><msub><mi>c</mi><mi>j</mi></msub><mo>+</mo><msub><mi>c</mi><mi>k</mi></msub></mrow><annotation encoding="application/x-tex">c_i+c_j+c_k</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.7333em;vertical-align:-0.15em;"></span><span class="mord"><span class="mord mathnormal">c</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">i</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mspace" style="margin-right:0.2222em;"></span><span class="mbin">+</span><span class="mspace" style="margin-right:0.2222em;"></span></span><span class="base"><span class="strut" style="height:0.8694em;vertical-align:-0.2861em;"></span><span class="mord"><span class="mord mathnormal">c</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight" style="margin-right:0.05724em;">j</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.2861em;"><span></span></span></span></span></span></span><span class="mspace" style="margin-right:0.2222em;"></span><span class="mbin">+</span><span class="mspace" style="margin-right:0.2222em;"></span></span><span class="base"><span class="strut" style="height:0.5806em;vertical-align:-0.15em;"></span><span class="mord"><span class="mord mathnormal">c</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3361em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight" style="margin-right:0.03148em;">k</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span></span></span></span> 的最小可能值。</p><h2 id="输入格式-163"><strong>输入格式</strong></h2><p>第一行包含整数 n。</p><p>第二行包含 n 个整数 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><msub><mi>s</mi><mn>1</mn></msub><mo separator="true">,</mo><msub><mi>s</mi><mn>2</mn></msub><mo separator="true">,</mo><mo>…</mo><mo separator="true">,</mo><msub><mi>s</mi><mi>n</mi></msub></mrow><annotation encoding="application/x-tex">s_1,s_2,…,s_n</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.625em;vertical-align:-0.1944em;"></span><span class="mord"><span class="mord mathnormal">s</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3011em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">1</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord mathnormal">s</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3011em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">2</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="minner">…</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord mathnormal">s</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.1514em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">n</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span></span></span></span>。</p><p>第三行包含 n 个整数 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><msub><mi>c</mi><mn>1</mn></msub><mo separator="true">,</mo><msub><mi>c</mi><mn>2</mn></msub><mo separator="true">,</mo><mo>…</mo><mo separator="true">,</mo><msub><mi>c</mi><mi>n</mi></msub></mrow><annotation encoding="application/x-tex">c_1,c_2,…,c_n</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.625em;vertical-align:-0.1944em;"></span><span class="mord"><span class="mord mathnormal">c</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3011em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">1</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord mathnormal">c</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3011em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">2</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="minner">…</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord mathnormal">c</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.1514em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">n</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span></span></span></span>。</p><h2 id="输出格式-163"><strong>输出格式</strong></h2><p>如果满足条件的三元组不存在，则输出 −1。</p><p>否则，输出 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><msub><mi>c</mi><mi>i</mi></msub><mo>+</mo><msub><mi>c</mi><mi>j</mi></msub><mo>+</mo><msub><mi>c</mi><mi>k</mi></msub></mrow><annotation encoding="application/x-tex">c_i+c_j+c_k</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.7333em;vertical-align:-0.15em;"></span><span class="mord"><span class="mord mathnormal">c</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">i</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mspace" style="margin-right:0.2222em;"></span><span class="mbin">+</span><span class="mspace" style="margin-right:0.2222em;"></span></span><span class="base"><span class="strut" style="height:0.8694em;vertical-align:-0.2861em;"></span><span class="mord"><span class="mord mathnormal">c</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight" style="margin-right:0.05724em;">j</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.2861em;"><span></span></span></span></span></span></span><span class="mspace" style="margin-right:0.2222em;"></span><span class="mbin">+</span><span class="mspace" style="margin-right:0.2222em;"></span></span><span class="base"><span class="strut" style="height:0.5806em;vertical-align:-0.15em;"></span><span class="mord"><span class="mord mathnormal">c</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3361em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight" style="margin-right:0.03148em;">k</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span></span></span></span> 的最小可能值。</p><h2 id="数据范围-189"><strong>数据范围</strong></h2><p>前 5 个测试点满足 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mn>3</mn><mo>≤</mo><mi>n</mi><mo>≤</mo><mn>10</mn></mrow><annotation encoding="application/x-tex">3≤n≤10</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.7804em;vertical-align:-0.136em;"></span><span class="mord">3</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.7719em;vertical-align:-0.136em;"></span><span class="mord mathnormal">n</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.6444em;"></span><span class="mord">10</span></span></span></span>。<br>所有测试点满足 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mn>3</mn><mo>≤</mo><mi>n</mi><mo>≤</mo><mn>3000</mn><mtext>，</mtext><mn>1</mn><mo>≤</mo><msub><mi>s</mi><mi>i</mi></msub><mo>≤</mo><mn>1</mn><msup><mn>0</mn><mn>9</mn></msup><mtext>，</mtext><mn>1</mn><mo>≤</mo><msub><mi>c</mi><mi>i</mi></msub><mo>≤</mo><mn>1</mn><msup><mn>0</mn><mn>8</mn></msup></mrow><annotation encoding="application/x-tex">3≤n≤3000，1≤s_i≤10^9，1≤c_i≤10^8</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.7804em;vertical-align:-0.136em;"></span><span class="mord">3</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.7719em;vertical-align:-0.136em;"></span><span class="mord mathnormal">n</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.8193em;vertical-align:-0.136em;"></span><span class="mord">3000</span><span class="mord cjk_fallback">，</span><span class="mord">1</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.786em;vertical-align:-0.15em;"></span><span class="mord"><span class="mord mathnormal">s</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">i</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.9501em;vertical-align:-0.136em;"></span><span class="mord">1</span><span class="mord"><span class="mord">0</span><span class="msupsub"><span class="vlist-t"><span class="vlist-r"><span class="vlist" style="height:0.8141em;"><span style="top:-3.063em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">9</span></span></span></span></span></span></span></span><span class="mord cjk_fallback">，</span><span class="mord">1</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.786em;vertical-align:-0.15em;"></span><span class="mord"><span class="mord mathnormal">c</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">i</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.8141em;"></span><span class="mord">1</span><span class="mord"><span class="mord">0</span><span class="msupsub"><span class="vlist-t"><span class="vlist-r"><span class="vlist" style="height:0.8141em;"><span style="top:-3.063em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">8</span></span></span></span></span></span></span></span></span></span></span>。</p><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br></pre></td><td class="code"><pre><span class="line">输入样例<span class="number">1</span>：</span><br><span class="line"><span class="number">5</span></span><br><span class="line"><span class="number">2</span> <span class="number">4</span> <span class="number">5</span> <span class="number">4</span> <span class="number">10</span></span><br><span class="line"><span class="number">40</span> <span class="number">30</span> <span class="number">20</span> <span class="number">10</span> <span class="number">40</span></span><br><span class="line"></span><br><span class="line">输出样例<span class="number">1</span>：</span><br><span class="line"><span class="number">90</span></span><br><span class="line"></span><br><span class="line">输入样例<span class="number">2</span>：</span><br><span class="line"><span class="number">3</span></span><br><span class="line"><span class="number">100</span> <span class="number">101</span> <span class="number">100</span></span><br><span class="line"><span class="number">2</span> <span class="number">4</span> <span class="number">5</span></span><br><span class="line"></span><br><span class="line">输出样例<span class="number">2</span>：</span><br><span class="line"><span class="number">-1</span></span><br><span class="line"></span><br><span class="line">输入样例<span class="number">3</span>：</span><br><span class="line"><span class="number">10</span></span><br><span class="line"><span class="number">1</span> <span class="number">2</span> <span class="number">3</span> <span class="number">4</span> <span class="number">5</span> <span class="number">6</span> <span class="number">7</span> <span class="number">8</span> <span class="number">9</span> <span class="number">10</span></span><br><span class="line"><span class="number">10</span> <span class="number">13</span> <span class="number">11</span> <span class="number">14</span> <span class="number">15</span> <span class="number">12</span> <span class="number">13</span> <span class="number">13</span> <span class="number">18</span> <span class="number">13</span></span><br><span class="line"></span><br><span class="line">输出样例<span class="number">3</span>：</span><br><span class="line"><span class="number">33</span></span><br></pre></td></tr></table></figure><h2 id="分析-141"><strong>分析</strong></h2><ol><li>i,j,k，如果三个都遍历的话时间就用<span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><msup><mi>n</mi><mn>3</mn></msup></mrow><annotation encoding="application/x-tex">n^3</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.8141em;"></span><span class="mord"><span class="mord mathnormal">n</span><span class="msupsub"><span class="vlist-t"><span class="vlist-r"><span class="vlist" style="height:0.8141em;"><span style="top:-3.063em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">3</span></span></span></span></span></span></span></span></span></span></span>，大约是<span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mn>9</mn><mo>∗</mo><mn>1</mn><msup><mn>0</mn><mn>9</mn></msup></mrow><annotation encoding="application/x-tex">9*10^9</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.6444em;"></span><span class="mord">9</span><span class="mspace" style="margin-right:0.2222em;"></span><span class="mbin">∗</span><span class="mspace" style="margin-right:0.2222em;"></span></span><span class="base"><span class="strut" style="height:0.8141em;"></span><span class="mord">1</span><span class="mord"><span class="mord">0</span><span class="msupsub"><span class="vlist-t"><span class="vlist-r"><span class="vlist" style="height:0.8141em;"><span style="top:-3.063em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">9</span></span></span></span></span></span></span></span></span></span></span>肯定会超时</li><li>如果第一层遍历j的话，那么<span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mn>0</mn><mo><</mo><mi>i</mi><mo><</mo><mi>j</mi></mrow><annotation encoding="application/x-tex">0<i<j</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.6835em;vertical-align:-0.0391em;"></span><span class="mord">0</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel"><</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.6986em;vertical-align:-0.0391em;"></span><span class="mord mathnormal">i</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel"><</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.854em;vertical-align:-0.1944em;"></span><span class="mord mathnormal" style="margin-right:0.05724em;">j</span></span></span></span>并且<span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>j</mi><mo><</mo><mi>k</mi><mo><</mo><mi>n</mi></mrow><annotation encoding="application/x-tex">j<k<n</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.854em;vertical-align:-0.1944em;"></span><span class="mord mathnormal" style="margin-right:0.05724em;">j</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel"><</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.7335em;vertical-align:-0.0391em;"></span><span class="mord mathnormal" style="margin-right:0.03148em;">k</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel"><</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.4306em;"></span><span class="mord mathnormal">n</span></span></span></span>，这样就把数组分成了两段</li><li>想要<span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><msub><mi>c</mi><mi>i</mi></msub><mo>+</mo><msub><mi>c</mi><mi>j</mi></msub><mo>+</mo><msub><mi>c</mi><mi>k</mi></msub></mrow><annotation encoding="application/x-tex">c_i+c_j+c_k</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.7333em;vertical-align:-0.15em;"></span><span class="mord"><span class="mord mathnormal">c</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">i</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mspace" style="margin-right:0.2222em;"></span><span class="mbin">+</span><span class="mspace" style="margin-right:0.2222em;"></span></span><span class="base"><span class="strut" style="height:0.8694em;vertical-align:-0.2861em;"></span><span class="mord"><span class="mord mathnormal">c</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight" style="margin-right:0.05724em;">j</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.2861em;"><span></span></span></span></span></span></span><span class="mspace" style="margin-right:0.2222em;"></span><span class="mbin">+</span><span class="mspace" style="margin-right:0.2222em;"></span></span><span class="base"><span class="strut" style="height:0.5806em;vertical-align:-0.15em;"></span><span class="mord"><span class="mord mathnormal">c</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3361em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight" style="margin-right:0.03148em;">k</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span></span></span></span>最小，而<span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><msub><mi>c</mi><mi>j</mi></msub></mrow><annotation encoding="application/x-tex">c_j</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.7167em;vertical-align:-0.2861em;"></span><span class="mord"><span class="mord mathnormal">c</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight" style="margin-right:0.05724em;">j</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.2861em;"><span></span></span></span></span></span></span></span></span></span>是遍历出来的，那么只要把<span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><msub><mi>c</mi><mi>i</mi></msub></mrow><annotation encoding="application/x-tex">c_i</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.5806em;vertical-align:-0.15em;"></span><span class="mord"><span class="mord mathnormal">c</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">i</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span></span></span></span>和<span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><msub><mi>c</mi><mi>k</mi></msub></mrow><annotation encoding="application/x-tex">c_k</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.5806em;vertical-align:-0.15em;"></span><span class="mord"><span class="mord mathnormal">c</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3361em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight" style="margin-right:0.03148em;">k</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span></span></span></span>在各自的分段中取到最小，然后就可以找到固定<span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><msub><mi>c</mi><mi>j</mi></msub></mrow><annotation encoding="application/x-tex">c_j</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.7167em;vertical-align:-0.2861em;"></span><span class="mord"><span class="mord mathnormal">c</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight" style="margin-right:0.05724em;">j</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.2861em;"><span></span></span></span></span></span></span></span></span></span>时的<span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><msub><mi>c</mi><mi>i</mi></msub><mo>+</mo><msub><mi>c</mi><mi>j</mi></msub><mo>+</mo><msub><mi>c</mi><mi>k</mi></msub></mrow><annotation encoding="application/x-tex">c_i+c_j+c_k</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.7333em;vertical-align:-0.15em;"></span><span class="mord"><span class="mord mathnormal">c</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">i</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mspace" style="margin-right:0.2222em;"></span><span class="mbin">+</span><span class="mspace" style="margin-right:0.2222em;"></span></span><span class="base"><span class="strut" style="height:0.8694em;vertical-align:-0.2861em;"></span><span class="mord"><span class="mord mathnormal">c</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight" style="margin-right:0.05724em;">j</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.2861em;"><span></span></span></span></span></span></span><span class="mspace" style="margin-right:0.2222em;"></span><span class="mbin">+</span><span class="mspace" style="margin-right:0.2222em;"></span></span><span class="base"><span class="strut" style="height:0.5806em;vertical-align:-0.15em;"></span><span class="mord"><span class="mord mathnormal">c</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3361em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight" style="margin-right:0.03148em;">k</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span></span></span></span>最小，然后从j遍历的各次中找到<span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><msub><mi>c</mi><mi>i</mi></msub><mo>+</mo><msub><mi>c</mi><mi>j</mi></msub><mo>+</mo><msub><mi>c</mi><mi>k</mi></msub></mrow><annotation encoding="application/x-tex">c_i+c_j+c_k</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.7333em;vertical-align:-0.15em;"></span><span class="mord"><span class="mord mathnormal">c</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">i</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mspace" style="margin-right:0.2222em;"></span><span class="mbin">+</span><span class="mspace" style="margin-right:0.2222em;"></span></span><span class="base"><span class="strut" style="height:0.8694em;vertical-align:-0.2861em;"></span><span class="mord"><span class="mord mathnormal">c</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight" style="margin-right:0.05724em;">j</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.2861em;"><span></span></span></span></span></span></span><span class="mspace" style="margin-right:0.2222em;"></span><span class="mbin">+</span><span class="mspace" style="margin-right:0.2222em;"></span></span><span class="base"><span class="strut" style="height:0.5806em;vertical-align:-0.15em;"></span><span class="mord"><span class="mord mathnormal">c</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3361em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight" style="margin-right:0.03148em;">k</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span></span></span></span>最小就可以了</li></ol><h2 id="解答-192"><strong>解答</strong></h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br><span class="line">24</span><br><span class="line">25</span><br><span class="line">26</span><br><span class="line">27</span><br><span class="line">28</span><br><span class="line">29</span><br><span class="line">30</span><br><span class="line">31</span><br><span class="line">32</span><br><span class="line">33</span><br><span class="line">34</span><br><span class="line">35</span><br><span class="line">36</span><br><span class="line">37</span><br><span class="line">38</span><br><span class="line">39</span><br><span class="line">40</span><br><span class="line">41</span><br><span class="line">42</span><br><span class="line">43</span><br><span class="line">44</span><br></pre></td><td class="code"><pre><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><iostream></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><cstring></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><algorithm></span></span></span><br><span class="line"></span><br><span class="line"><span class="keyword">using</span> <span class="keyword">namespace</span> std;</span><br><span class="line"></span><br><span class="line"><span class="type">const</span> <span class="type">int</span> N = <span class="number">3010</span>,INF=<span class="number">5e8</span>;</span><br><span class="line"></span><br><span class="line"><span class="type">int</span> c[N],s[N];</span><br><span class="line"></span><br><span class="line"><span class="type">int</span> n,ans=INF;</span><br><span class="line"></span><br><span class="line"><span class="function"><span class="type">void</span> <span class="title">Enum</span><span class="params">()</span></span>{</span><br><span class="line"> <span class="keyword">for</span> (<span class="type">int</span> j = <span class="number">1</span>; j <= n<span class="number">-2</span>; j ++ ){</span><br><span class="line"> <span class="type">int</span> iMin=INF,kMin=INF;</span><br><span class="line"> <span class="keyword">for</span> (<span class="type">int</span> i = <span class="number">0</span>; i < j; i ++ )</span><br><span class="line"> <span class="keyword">if</span>(s[i]<s[j]) </span><br><span class="line"> iMin=<span class="built_in">min</span>(iMin,c[i]);</span><br><span class="line"> </span><br><span class="line"> <span class="keyword">for</span> (<span class="type">int</span> k = j+<span class="number">1</span>; k < n; k ++ )</span><br><span class="line"> <span class="keyword">if</span>(s[k]>s[j]) </span><br><span class="line"> kMin=<span class="built_in">min</span>(kMin,c[k]);</span><br><span class="line"> </span><br><span class="line"> <span class="keyword">if</span>(iMin!=INF&&kMin!=INF)</span><br><span class="line"> ans=<span class="built_in">min</span>(ans,iMin+c[j]+kMin);</span><br><span class="line"> }</span><br><span class="line">}</span><br><span class="line"></span><br><span class="line"><span class="function"><span class="type">int</span> <span class="title">main</span><span class="params">()</span></span>{</span><br><span class="line"> <span class="built_in">scanf</span>(<span class="string">"%d"</span>, &n);</span><br><span class="line"> </span><br><span class="line"> <span class="keyword">for</span> (<span class="type">int</span> i = <span class="number">0</span>; i < n; i ++ )</span><br><span class="line"> <span class="built_in">scanf</span>(<span class="string">"%d"</span>, &s[i]);</span><br><span class="line"> </span><br><span class="line"> <span class="keyword">for</span> (<span class="type">int</span> i = <span class="number">0</span>; i < n; i ++ )</span><br><span class="line"> <span class="built_in">scanf</span>(<span class="string">"%d"</span>, &c[i]);</span><br><span class="line"> </span><br><span class="line"> <span class="built_in">Enum</span>();</span><br><span class="line"> </span><br><span class="line"> <span class="keyword">if</span>(ans==INF) <span class="built_in">printf</span>(<span class="string">"%d"</span>,<span class="number">-1</span>);</span><br><span class="line"> <span class="keyword">else</span> <span class="built_in">printf</span>(<span class="string">"%d"</span>,ans);</span><br><span class="line"> </span><br><span class="line"> <span class="keyword">return</span> <span class="number">0</span>;</span><br><span class="line">}</span><br></pre></td></tr></table></figure>]]></content>
<summary type="html"><h2 id="题目-174"><strong>题目</strong></h2>
<p>给定两个长度为 n 的整数序列 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/19</summary>
<category term="算法" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/"/>
<category term="Acwing" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/Acwing/"/>
<category term="Acwing周赛" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/Acwing/Acwing%E5%91%A8%E8%B5%9B/"/>
</entry>
<entry>
<title>4213-最小结果</title>
<link href="http://example.com/2022/07/16/algorithm/Acwing/WeeklyMatches/WeeklyMatches35/4213_%E6%9C%80%E5%B0%8F%E7%BB%93%E6%9E%9C/"/>
<id>http://example.com/2022/07/16/algorithm/Acwing/WeeklyMatches/WeeklyMatches35/4213_%E6%9C%80%E5%B0%8F%E7%BB%93%E6%9E%9C/</id>
<published>2022-07-16T03:25:18.901Z</published>
<updated>2022-07-16T12:26:15.608Z</updated>
<content type="html"><![CDATA[<h2 id="题目-175"><strong>题目</strong></h2><p>有四个整数 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>a</mi><mo separator="true">,</mo><mi>b</mi><mo separator="true">,</mo><mi>c</mi><mo separator="true">,</mo><mi>d</mi></mrow><annotation encoding="application/x-tex">a,b,c,d</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.8889em;vertical-align:-0.1944em;"></span><span class="mord mathnormal">a</span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord mathnormal">b</span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord mathnormal">c</span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord mathnormal">d</span></span></span></span>。</p><p>有三个操作符 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>o</mi><mi>p</mi><mn>1</mn><mo separator="true">,</mo><mi>o</mi><mi>p</mi><mn>2</mn><mo separator="true">,</mo><mi>o</mi><mi>p</mi><mn>3</mn></mrow><annotation encoding="application/x-tex">op1,op2,op3</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.8389em;vertical-align:-0.1944em;"></span><span class="mord mathnormal">o</span><span class="mord mathnormal">p</span><span class="mord">1</span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord mathnormal">o</span><span class="mord mathnormal">p</span><span class="mord">2</span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord mathnormal">o</span><span class="mord mathnormal">p</span><span class="mord">3</span></span></span></span>，每个操作符要么是 *（表示乘法），要么是 +（表示加法）。</p><p>现在，我们要进行如下操作：</p><ol><li>从现有整数中选出两个，按 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>o</mi><mi>p</mi><mn>1</mn></mrow><annotation encoding="application/x-tex">op1</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.8389em;vertical-align:-0.1944em;"></span><span class="mord mathnormal">o</span><span class="mord mathnormal">p</span><span class="mord">1</span></span></span></span> 进行运算，得到结果。将选出的两个整数舍弃，并将结果保留。此时我们还剩下三个整数。</li><li>从现有整数中选出两个，按 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>o</mi><mi>p</mi><mn>2</mn></mrow><annotation encoding="application/x-tex">op2</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.8389em;vertical-align:-0.1944em;"></span><span class="mord mathnormal">o</span><span class="mord mathnormal">p</span><span class="mord">2</span></span></span></span> 进行运算，得到结果。将选出的两个整数舍弃，并将结果保留。此时我们还剩下两个整数。</li><li>从现有整数中选出两个，按 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>o</mi><mi>p</mi><mn>3</mn></mrow><annotation encoding="application/x-tex">op3</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.8389em;vertical-align:-0.1944em;"></span><span class="mord mathnormal">o</span><span class="mord mathnormal">p</span><span class="mord">3</span></span></span></span> 进行运算，得到结果。将选出的两个整数舍弃，并将结果保留。此时我们只剩下一个整数。</li></ol><p>我们希望，最后剩下的一个整数尽可能小。</p><h2 id="输入格式-164"><strong>输入格式</strong></h2><p>第一行包含四个整数 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>a</mi><mo separator="true">,</mo><mi>b</mi><mo separator="true">,</mo><mi>c</mi><mo separator="true">,</mo><mi>d</mi></mrow><annotation encoding="application/x-tex">a,b,c,d</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.8889em;vertical-align:-0.1944em;"></span><span class="mord mathnormal">a</span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord mathnormal">b</span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord mathnormal">c</span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord mathnormal">d</span></span></span></span>。</p><p>第二行包含三个操作符 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>o</mi><mi>p</mi><mn>1</mn><mo separator="true">,</mo><mi>o</mi><mi>p</mi><mn>2</mn><mo separator="true">,</mo><mi>o</mi><mi>p</mi><mn>3</mn></mrow><annotation encoding="application/x-tex">op1,op2,op3</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.8389em;vertical-align:-0.1944em;"></span><span class="mord mathnormal">o</span><span class="mord mathnormal">p</span><span class="mord">1</span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord mathnormal">o</span><span class="mord mathnormal">p</span><span class="mord">2</span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord mathnormal">o</span><span class="mord mathnormal">p</span><span class="mord">3</span></span></span></span>，每个操作符要么是 *，要么是 +。</p><h2 id="输出格式-164"><strong>输出格式</strong></h2><p>输出最后剩下的一个整数的最小可能值。</p><h2 id="数据范围-190"><strong>数据范围</strong></h2><p>所有测试点满足 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mn>0</mn><mo>≤</mo><mi>a</mi><mo separator="true">,</mo><mi>b</mi><mo separator="true">,</mo><mi>c</mi><mo separator="true">,</mo><mi>d</mi><mo>≤</mo><mn>1000</mn></mrow><annotation encoding="application/x-tex">0≤a,b,c,d≤1000</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.7804em;vertical-align:-0.136em;"></span><span class="mord">0</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.8889em;vertical-align:-0.1944em;"></span><span class="mord mathnormal">a</span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord mathnormal">b</span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord mathnormal">c</span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord mathnormal">d</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.6444em;"></span><span class="mord">1000</span></span></span></span>。</p><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br></pre></td><td class="code"><pre><span class="line">输入样例<span class="number">1</span>：</span><br><span class="line"><span class="number">1</span> <span class="number">1</span> <span class="number">1</span> <span class="number">1</span></span><br><span class="line">+ + *</span><br><span class="line"></span><br><span class="line">输出样例<span class="number">1</span>：</span><br><span class="line"><span class="number">3</span></span><br><span class="line"></span><br><span class="line">输入样例<span class="number">2</span>：</span><br><span class="line"><span class="number">2</span> <span class="number">2</span> <span class="number">2</span> <span class="number">2</span></span><br><span class="line">* * +</span><br><span class="line"></span><br><span class="line">输出样例<span class="number">2</span>：</span><br><span class="line"><span class="number">8</span></span><br><span class="line"></span><br><span class="line">输入样例<span class="number">3</span>：</span><br><span class="line"><span class="number">1</span> <span class="number">2</span> <span class="number">3</span> <span class="number">4</span></span><br><span class="line">* + +</span><br><span class="line"></span><br><span class="line">输出样例<span class="number">3</span>：</span><br><span class="line"><span class="number">9</span></span><br></pre></td></tr></table></figure><h2 id="分析-142"><strong>分析</strong></h2><p>数据较少，最多也只有 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><msubsup><mi>C</mi><mn>4</mn><mn>2</mn></msubsup><mo>×</mo><msubsup><mi>C</mi><mn>3</mn><mn>2</mn></msubsup><mo>×</mo><msubsup><mi>C</mi><mn>2</mn><mn>2</mn></msubsup><mo>=</mo><mn>18</mn></mrow><annotation encoding="application/x-tex">C^2_4×C^2_3×C^2_2=18</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:1.0622em;vertical-align:-0.2481em;"></span><span class="mord"><span class="mord mathnormal" style="margin-right:0.07153em;">C</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.8141em;"><span style="top:-2.4519em;margin-left:-0.0715em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">4</span></span></span><span style="top:-3.063em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">2</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.2481em;"><span></span></span></span></span></span></span><span class="mspace" style="margin-right:0.2222em;"></span><span class="mbin">×</span><span class="mspace" style="margin-right:0.2222em;"></span></span><span class="base"><span class="strut" style="height:1.0622em;vertical-align:-0.2481em;"></span><span class="mord"><span class="mord mathnormal" style="margin-right:0.07153em;">C</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.8141em;"><span style="top:-2.4519em;margin-left:-0.0715em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">3</span></span></span><span style="top:-3.063em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">2</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.2481em;"><span></span></span></span></span></span></span><span class="mspace" style="margin-right:0.2222em;"></span><span class="mbin">×</span><span class="mspace" style="margin-right:0.2222em;"></span></span><span class="base"><span class="strut" style="height:1.0622em;vertical-align:-0.2481em;"></span><span class="mord"><span class="mord mathnormal" style="margin-right:0.07153em;">C</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.8141em;"><span style="top:-2.4519em;margin-left:-0.0715em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">2</span></span></span><span style="top:-3.063em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">2</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.2481em;"><span></span></span></span></span></span></span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">=</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.6444em;"></span><span class="mord">18</span></span></span></span> 种方案,可以用dfs直接暴搜，每次挑选出两个数运算成一个数，和剩余的数组成一个新的数组，进入下一层的dfs</p><h2 id="解答-193"><strong>解答</strong></h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br><span class="line">24</span><br><span class="line">25</span><br><span class="line">26</span><br><span class="line">27</span><br><span class="line">28</span><br><span class="line">29</span><br><span class="line">30</span><br><span class="line">31</span><br><span class="line">32</span><br><span class="line">33</span><br><span class="line">34</span><br><span class="line">35</span><br><span class="line">36</span><br><span class="line">37</span><br><span class="line">38</span><br><span class="line">39</span><br><span class="line">40</span><br></pre></td><td class="code"><pre><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><iostream></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><cstring></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><algorithm></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><vector></span></span></span><br><span class="line"></span><br><span class="line"><span class="keyword">using</span> <span class="keyword">namespace</span> std;</span><br><span class="line"></span><br><span class="line"><span class="keyword">typedef</span> <span class="type">long</span> <span class="type">long</span> LL;</span><br><span class="line"><span class="type">char</span> op[<span class="number">5</span>];</span><br><span class="line">LL ans=<span class="number">1e13</span>;</span><br><span class="line"></span><br><span class="line"><span class="function"><span class="type">void</span> <span class="title">dfs</span><span class="params">(vector<LL> a,<span class="type">int</span> u)</span></span>{</span><br><span class="line"> <span class="keyword">if</span>(a.<span class="built_in">size</span>()==<span class="number">1</span>) ans=<span class="built_in">min</span>(a[<span class="number">0</span>],ans);</span><br><span class="line"> <span class="keyword">for</span> (<span class="type">int</span> i = <span class="number">0</span>; i < a.<span class="built_in">size</span>(); i ++ )</span><br><span class="line"> <span class="keyword">for</span> (<span class="type">int</span> j = i+<span class="number">1</span>; j < a.<span class="built_in">size</span>(); j ++ ){</span><br><span class="line"> </span><br><span class="line"> vector<LL> tmp;</span><br><span class="line"> <span class="keyword">for</span> (<span class="type">int</span> k = <span class="number">0</span>; k < a.<span class="built_in">size</span>(); k ++ )</span><br><span class="line"> <span class="keyword">if</span>(k!=i&&k!=j) tmp.<span class="built_in">push_back</span>(a[k]);</span><br><span class="line"> </span><br><span class="line"> <span class="keyword">if</span>(op[u]==<span class="string">'*'</span>) tmp.<span class="built_in">push_back</span>(a[i]*a[j]);</span><br><span class="line"> <span class="keyword">else</span> <span class="keyword">if</span>(op[u]==<span class="string">'+'</span>) tmp.<span class="built_in">push_back</span>(a[i]+a[j]);</span><br><span class="line"> </span><br><span class="line"> <span class="built_in">dfs</span>(tmp,u+<span class="number">1</span>);</span><br><span class="line"> }</span><br><span class="line"> </span><br><span class="line">}</span><br><span class="line"></span><br><span class="line"><span class="function"><span class="type">int</span> <span class="title">main</span><span class="params">()</span></span></span><br><span class="line"><span class="function"></span>{</span><br><span class="line"> <span class="function">vector<LL> <span class="title">a</span><span class="params">(<span class="number">4</span>)</span></span>;</span><br><span class="line"> <span class="keyword">for</span> (<span class="type">int</span> i = <span class="number">0</span>; i < <span class="number">4</span>; i ++ )</span><br><span class="line"> <span class="built_in">scanf</span>(<span class="string">"%lld"</span>, &a[i]);</span><br><span class="line"> </span><br><span class="line"> <span class="keyword">for</span> (<span class="type">int</span> i = <span class="number">0</span>; i < <span class="number">3</span>; i ++ )</span><br><span class="line"> cin>>op[i];<span class="comment">//要注意一下字符串的输入，cin可以过滤掉空格，而scanf不行.</span></span><br><span class="line"> </span><br><span class="line"> <span class="built_in">dfs</span>(a,<span class="number">0</span>);</span><br><span class="line"> <span class="built_in">printf</span>(<span class="string">"%lld"</span>,ans);</span><br><span class="line">}</span><br></pre></td></tr></table></figure>]]></content>
<summary type="html"><h2 id="题目-175"><strong>题目</strong></h2>
<p>有四个整数 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/Ma</summary>
<category term="算法" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/"/>
<category term="Acwing" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/Acwing/"/>
<category term="Acwing周赛" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/Acwing/Acwing%E5%91%A8%E8%B5%9B/"/>
</entry>
<entry>
<title>4212-字符串比较</title>
<link href="http://example.com/2022/07/16/algorithm/Acwing/WeeklyMatches/WeeklyMatches35/4212_%E5%AD%97%E7%AC%A6%E4%B8%B2%E6%AF%94%E8%BE%83/"/>
<id>http://example.com/2022/07/16/algorithm/Acwing/WeeklyMatches/WeeklyMatches35/4212_%E5%AD%97%E7%AC%A6%E4%B8%B2%E6%AF%94%E8%BE%83/</id>
<published>2022-07-16T03:25:18.898Z</published>
<updated>2022-07-16T12:26:15.608Z</updated>
<content type="html"><![CDATA[<h2 id="题目-173"><strong>题目</strong></h2><p>给定两个长度相等的由大小写英文字母构成的字符串 A 和 B。</p><p>请你按照字典顺序对这两个字符串进行比较。</p><p>注意，在进行比较时，字母的大小写无关紧要，即大写字母被认为等同于相应的小写字母。</p><h2 id="输入格式-162"><strong>输入格式</strong></h2><p>第一行，字符串 A。</p><p>第二行，字符串 B。</p><h2 id="输出格式-162"><strong>输出格式</strong></h2><p><span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mtext>如果</mtext><mi>A</mi><mo>></mo><mi>B</mi><mtext>，则输出</mtext><mn>1</mn><mtext>，如果</mtext><mi>A</mi><mo><</mo><mi>B</mi><mtext>，则输出</mtext><mo>−</mo><mn>1</mn><mtext>，如果</mtext><mi>A</mi><mo>=</mo><mi>B</mi><mtext>，则输出</mtext><mn>0</mn></mrow><annotation encoding="application/x-tex">如果 A>B，则输出 1，如果 A<B，则输出 −1，如果 A=B，则输出 0</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.7224em;vertical-align:-0.0391em;"></span><span class="mord cjk_fallback">如果</span><span class="mord mathnormal">A</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">></span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.7224em;vertical-align:-0.0391em;"></span><span class="mord mathnormal" style="margin-right:0.05017em;">B</span><span class="mord cjk_fallback">，则输出</span><span class="mord">1</span><span class="mord cjk_fallback">，如果</span><span class="mord mathnormal">A</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel"><</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.7667em;vertical-align:-0.0833em;"></span><span class="mord mathnormal" style="margin-right:0.05017em;">B</span><span class="mord cjk_fallback">，则输出</span><span class="mspace" style="margin-right:0.2222em;"></span><span class="mbin">−</span><span class="mspace" style="margin-right:0.2222em;"></span></span><span class="base"><span class="strut" style="height:0.6833em;"></span><span class="mord">1</span><span class="mord cjk_fallback">，如果</span><span class="mord mathnormal">A</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">=</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.6833em;"></span><span class="mord mathnormal" style="margin-right:0.05017em;">B</span><span class="mord cjk_fallback">，则输出</span><span class="mord">0</span></span></span></span>。</p><h2 id="数据范围-188"><strong>数据范围</strong></h2><p>所有测试点满足，<span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mn>1</mn><mo>≤</mo><mi mathvariant="normal">∣</mi><mi>A</mi><mi mathvariant="normal">∣</mi><mo separator="true">,</mo><mi mathvariant="normal">∣</mi><mi>B</mi><mi mathvariant="normal">∣</mi><mo>≤</mo><mn>100</mn></mrow><annotation encoding="application/x-tex">1≤|A|,|B|≤100</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.7804em;vertical-align:-0.136em;"></span><span class="mord">1</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:1em;vertical-align:-0.25em;"></span><span class="mord">∣</span><span class="mord mathnormal">A</span><span class="mord">∣</span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord">∣</span><span class="mord mathnormal" style="margin-right:0.05017em;">B</span><span class="mord">∣</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.6444em;"></span><span class="mord">100</span></span></span></span>。</p><h2 id="输入样例1-7"><strong>输入样例1</strong></h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br></pre></td><td class="code"><pre><span class="line">aaaa</span><br><span class="line">aaaA</span><br></pre></td></tr></table></figure><h2 id="输出样例1-7"><strong>输出样例1</strong></h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line"><span class="number">0</span></span><br></pre></td></tr></table></figure><h2 id="输入样例2-7"><strong>输入样例2</strong></h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br></pre></td><td class="code"><pre><span class="line">abs</span><br><span class="line">Abz</span><br></pre></td></tr></table></figure><h2 id="输出样例2-7"><strong>输出样例2</strong></h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line"><span class="number">-1</span></span><br></pre></td></tr></table></figure><h2 id="输入样例3-3"><strong>输入样例3</strong></h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br></pre></td><td class="code"><pre><span class="line">abcdefg</span><br><span class="line">AbCdEfF</span><br></pre></td></tr></table></figure><h2 id="输出样例3-3"><strong>输出样例3</strong></h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line"><span class="number">1</span></span><br></pre></td></tr></table></figure><h2 id="解答-191"><strong>解答</strong></h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br><span class="line">24</span><br></pre></td><td class="code"><pre><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><iostream></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><cstring></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><algorithm></span></span></span><br><span class="line"></span><br><span class="line"><span class="keyword">using</span> <span class="keyword">namespace</span> std;</span><br><span class="line"></span><br><span class="line"><span class="function"><span class="type">void</span> <span class="title">to_low</span><span class="params">(string &str)</span></span>{</span><br><span class="line"> <span class="keyword">for</span> (<span class="type">int</span> i = <span class="number">0</span>; i < str.<span class="built_in">size</span>(); i ++ )</span><br><span class="line"> <span class="keyword">if</span>(str[i]>=<span class="string">'A'</span>&&str[i]<=<span class="string">'Z'</span>)</span><br><span class="line"> str[i]+=<span class="number">32</span>;</span><br><span class="line">}</span><br><span class="line"></span><br><span class="line"><span class="function"><span class="type">int</span> <span class="title">main</span><span class="params">()</span></span>{</span><br><span class="line"> string a,b;</span><br><span class="line"> cin>>a>>b;</span><br><span class="line"> </span><br><span class="line"> <span class="built_in">to_low</span>(a),<span class="built_in">to_low</span>(b);</span><br><span class="line"> </span><br><span class="line"> <span class="keyword">if</span>(a>b) cout << <span class="number">1</span> <<endl;</span><br><span class="line"> <span class="keyword">else</span> <span class="keyword">if</span>(a==b) cout << <span class="number">0</span> << endl;</span><br><span class="line"> <span class="keyword">else</span> cout << <span class="number">-1</span> <<endl;</span><br><span class="line"> </span><br><span class="line"> <span class="keyword">return</span> <span class="number">0</span>;</span><br><span class="line">}</span><br></pre></td></tr></table></figure>]]></content>
<summary type="html"><h2 id="题目-173"><strong>题目</strong></h2>
<p>给定两个长度相等的由大小写英文字母构成的字符串 A 和 B。</p>
<p>请你按照字典顺序对这两个字符串进行比较。</p>
<p>注意，在进行比较时，字母的大小写无关紧要，即大写字母被认为等</summary>
<category term="算法" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/"/>
<category term="Acwing" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/Acwing/"/>
<category term="Acwing周赛" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/Acwing/Acwing%E5%91%A8%E8%B5%9B/"/>
</entry>
<entry>
<title>4211-序列重排</title>
<link href="http://example.com/2022/07/16/algorithm/Acwing/WeeklyMatches/WeeklyMatches34/4211_%E5%BA%8F%E5%88%97%E9%87%8D%E6%8E%92/"/>
<id>http://example.com/2022/07/16/algorithm/Acwing/WeeklyMatches/WeeklyMatches34/4211_%E5%BA%8F%E5%88%97%E9%87%8D%E6%8E%92/</id>
<published>2022-07-16T03:25:18.893Z</published>
<updated>2022-07-16T12:26:15.608Z</updated>
<content type="html"><![CDATA[<h2 id="题目-170"><strong>题目</strong></h2><p>给定一个长度为 n 的整数序列 a1,a2,…,an。</p><p>请你对序列进行重新排序（也可以保持原序列），要求新序列满足每个元素（第 1 个除外）都恰好是前一个元素的两倍或前一个元素的三分之一。</p><p>保证输入一定有解。</p><h2 id="输入格式-158"><strong>输入格式</strong></h2><p>第一行包含整数 n。</p><p>第二行包含 n 个整数 a1,a2,…,an。</p><h2 id="输出格式-158"><strong>输出格式</strong></h2><p>一行 n 个整数，表示排序后的序列。输出任意合法方案即可。</p><h2 id="数据范围-184"><strong>数据范围</strong></h2><p>前三个测试点满足 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mn>2</mn><mo>≤</mo><mi>n</mi><mo>≤</mo><mn>10</mn><mtext>。</mtext></mrow><annotation encoding="application/x-tex">2≤n≤10。</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.7804em;vertical-align:-0.136em;"></span><span class="mord">2</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.7719em;vertical-align:-0.136em;"></span><span class="mord mathnormal">n</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.6833em;"></span><span class="mord">10</span><span class="mord cjk_fallback">。</span></span></span></span></p><p>所有测试点满足 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mn>2</mn><mo>≤</mo><mi>n</mi><mo>≤</mo><mn>100</mn><mtext>，</mtext><mn>1</mn><mo>≤</mo><msub><mi>a</mi><mi>i</mi></msub><mo>≤</mo><mn>3</mn><mo>×</mo><mn>1</mn><msup><mn>0</mn><mn>18</mn></msup></mrow><annotation encoding="application/x-tex">2≤n≤100，1≤a_i≤3×10^{18}</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.7804em;vertical-align:-0.136em;"></span><span class="mord">2</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.7719em;vertical-align:-0.136em;"></span><span class="mord mathnormal">n</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.8193em;vertical-align:-0.136em;"></span><span class="mord">100</span><span class="mord cjk_fallback">，</span><span class="mord">1</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.786em;vertical-align:-0.15em;"></span><span class="mord"><span class="mord mathnormal">a</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">i</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.7278em;vertical-align:-0.0833em;"></span><span class="mord">3</span><span class="mspace" style="margin-right:0.2222em;"></span><span class="mbin">×</span><span class="mspace" style="margin-right:0.2222em;"></span></span><span class="base"><span class="strut" style="height:0.8141em;"></span><span class="mord">1</span><span class="mord"><span class="mord">0</span><span class="msupsub"><span class="vlist-t"><span class="vlist-r"><span class="vlist" style="height:0.8141em;"><span style="top:-3.063em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight"><span class="mord mtight">18</span></span></span></span></span></span></span></span></span></span></span></span>。</p><h2 id="输入样例1-3"><strong>输入样例1</strong></h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br></pre></td><td class="code"><pre><span class="line"><span class="number">6</span></span><br><span class="line"><span class="number">4</span> <span class="number">8</span> <span class="number">6</span> <span class="number">3</span> <span class="number">12</span> <span class="number">9</span></span><br></pre></td></tr></table></figure><h2 id="输出样例1-3"><strong>输出样例1</strong></h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line"><span class="number">9</span> <span class="number">3</span> <span class="number">6</span> <span class="number">12</span> <span class="number">4</span> <span class="number">8</span></span><br></pre></td></tr></table></figure><h2 id="输入样例2-3"><strong>输入样例2</strong></h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br></pre></td><td class="code"><pre><span class="line"><span class="number">4</span></span><br><span class="line"><span class="number">42</span> <span class="number">28</span> <span class="number">84</span> <span class="number">126</span></span><br></pre></td></tr></table></figure><h2 id="输出样例2-3"><strong>输出样例2</strong></h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line"><span class="number">126</span> <span class="number">42</span> <span class="number">84</span> <span class="number">28</span></span><br></pre></td></tr></table></figure><h2 id="输入样例3"><strong>输入样例3</strong></h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br></pre></td><td class="code"><pre><span class="line"><span class="number">2</span></span><br><span class="line"><span class="number">1000000000000000000</span> <span class="number">3000000000000000000</span></span><br></pre></td></tr></table></figure><h2 id="输出样例3"><strong>输出样例3</strong></h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line"><span class="number">3000000000000000000</span> <span class="number">1000000000000000000</span></span><br></pre></td></tr></table></figure><h2 id="分析-140"><strong>分析</strong></h2><p>（1）必要性：由于这道题保障一定有解，我们可以倒推这样的序列满足的性质。题中给的条件是a[i] == a[i - 1] * 2或a[i] * 3 == a[i - 1]，所以这样的序列可以是按照包含2或者3的因子个数排列的，实际上，q[i] = {get(x, 2), -get(x, 3), x}还可以写成q[i] = {-get(x, 3), get(x, 2), x}。</p><p>（2）同时从（1）还可以推出满足条件的序列是唯一的（反证法）；</p><p>（3）充分性（也是这道题最巧妙的一环）：假设任取一个可行的序列，那么一定满足我们前面的性质，即a[i] == a[i - 1] * 2或a[i] * 3 == a[i - 1]，又因为满足该性质的序列是唯一的，所以这个任取一个可行的序列就是唯一的。</p><p>（4）综上所述，实际上题里声称的”输出任意合法方案即可“是虚晃一枪</p><h2 id="y总的解答，自己搞不倒"><strong>y总的解答，自己搞不倒</strong></h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br><span class="line">24</span><br><span class="line">25</span><br><span class="line">26</span><br><span class="line">27</span><br><span class="line">28</span><br><span class="line">29</span><br><span class="line">30</span><br><span class="line">31</span><br><span class="line">32</span><br><span class="line">33</span><br><span class="line">34</span><br><span class="line">35</span><br><span class="line">36</span><br><span class="line">37</span><br><span class="line">38</span><br><span class="line">39</span><br></pre></td><td class="code"><pre><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><iostream></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><cstring></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><algorithm></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><vector></span></span></span><br><span class="line"></span><br><span class="line"><span class="keyword">using</span> <span class="keyword">namespace</span> std;</span><br><span class="line"></span><br><span class="line"><span class="keyword">typedef</span> <span class="type">long</span> <span class="type">long</span> LL;</span><br><span class="line"></span><br><span class="line"><span class="type">const</span> <span class="type">int</span> N = <span class="number">110</span>;</span><br><span class="line"></span><br><span class="line"><span class="type">int</span> n;</span><br><span class="line">vector<LL> q[N];</span><br><span class="line"></span><br><span class="line"><span class="function"><span class="type">int</span> <span class="title">get</span><span class="params">(LL x, <span class="type">int</span> b)</span></span></span><br><span class="line"><span class="function"></span>{</span><br><span class="line"> <span class="type">int</span> res = <span class="number">0</span>;</span><br><span class="line"> <span class="keyword">while</span> (x % b == <span class="number">0</span>) res ++, x /= b;</span><br><span class="line"> <span class="keyword">return</span> res;</span><br><span class="line">}</span><br><span class="line"></span><br><span class="line"><span class="function"><span class="type">int</span> <span class="title">main</span><span class="params">()</span></span></span><br><span class="line"><span class="function"></span>{</span><br><span class="line"> cin >> n;</span><br><span class="line"> <span class="keyword">for</span> (<span class="type">int</span> i = <span class="number">0</span>; i < n; i ++ )</span><br><span class="line"> {</span><br><span class="line"> LL x;</span><br><span class="line"> cin >> x;</span><br><span class="line"> q[i] = {<span class="built_in">get</span>(x, <span class="number">2</span>), -<span class="built_in">get</span>(x, <span class="number">3</span>), x};<span class="comment">//每一个q[i]都是一个vector<LL>。</span></span><br><span class="line"> }</span><br><span class="line"></span><br><span class="line"> <span class="built_in">sort</span>(q, q + n);<span class="comment">//排序，按照关键字排序</span></span><br><span class="line"></span><br><span class="line"> <span class="keyword">for</span> (<span class="type">int</span> i = <span class="number">0</span>; i < n; i ++ )</span><br><span class="line"> cout << q[i][<span class="number">2</span>] << <span class="string">' '</span>;</span><br><span class="line"> cout << endl;</span><br><span class="line"></span><br><span class="line"> <span class="keyword">return</span> <span class="number">0</span>;</span><br><span class="line">}</span><br></pre></td></tr></table></figure>]]></content>
<summary type="html"><h2 id="题目-170"><strong>题目</strong></h2>
<p>给定一个长度为 n 的整数序列 a1,a2,…,an。</p>
<p>请你对序列进行重新排序（也可以保持原序列），要求新序列满足每个元素（第 1 个除外）都恰好是前一个元素的两倍或前一个元素的</summary>
<category term="算法" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/"/>
<category term="Acwing" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/Acwing/"/>
<category term="Acwing周赛" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/Acwing/Acwing%E5%91%A8%E8%B5%9B/"/>
</entry>
<entry>
<title>4210-数字</title>
<link href="http://example.com/2022/07/16/algorithm/Acwing/WeeklyMatches/WeeklyMatches34/4210_%E6%95%B0%E5%AD%97/"/>
<id>http://example.com/2022/07/16/algorithm/Acwing/WeeklyMatches/WeeklyMatches34/4210_%E6%95%B0%E5%AD%97/</id>
<published>2022-07-16T03:25:18.891Z</published>
<updated>2022-07-16T12:26:15.608Z</updated>
<content type="html"><![CDATA[<h2 id="题目-169"><strong>题目</strong></h2><p>给定一个大于 2 的十进制正整数 A。</p><p>该数字在 2∼A−1 进制表示下的各位数字之和均可以求出。</p><p>例如，数字 123 在 16 进制表示下，共有 2 位：第 1 位是 7，第二位是 11，各位数字之和为 18。</p><p>现在，请你将 A 在 2∼A−1 进制表示下的各位数字之和全部相加，并将得到的结果除以 A−2，最终结果以最简分数形式输出。</p><h2 id="输入格式-157"><strong>输入格式</strong></h2><p>一个十进制正整数 A。</p><h2 id="输出格式-157"><strong>输出格式</strong></h2><p>输出格式为 X/Y，其中 X 表示输出答案的分子，Y 表示输出答案的分母。</p><h2 id="数据范围-183"><strong>数据范围</strong></h2><p>前三个测试点满足 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mn>3</mn><mo>≤</mo><mi>A</mi><mo>≤</mo><mn>10</mn><mtext>。</mtext></mrow><annotation encoding="application/x-tex">3≤A≤10。</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.7804em;vertical-align:-0.136em;"></span><span class="mord">3</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.8193em;vertical-align:-0.136em;"></span><span class="mord mathnormal">A</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.6833em;"></span><span class="mord">10</span><span class="mord cjk_fallback">。</span></span></span></span><br>所有测试点满足 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mn>3</mn><mo>≤</mo><mi>A</mi><mo>≤</mo><mn>1000</mn><mtext>。</mtext></mrow><annotation encoding="application/x-tex">3≤A≤1000。</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.7804em;vertical-align:-0.136em;"></span><span class="mord">3</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.8193em;vertical-align:-0.136em;"></span><span class="mord mathnormal">A</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.6833em;"></span><span class="mord">1000</span><span class="mord cjk_fallback">。</span></span></span></span></p><h2 id="输入样例1-2"><strong>输入样例1</strong></h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line"><span class="number">5</span></span><br></pre></td></tr></table></figure><h2 id="输出样例1-2"><strong>输出样例1</strong></h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line"><span class="number">7</span>/<span class="number">3</span></span><br></pre></td></tr></table></figure><h2 id="输入样例2-2"><strong>输入样例2</strong></h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line"><span class="number">3</span></span><br></pre></td></tr></table></figure><h2 id="输出样例2-2"><strong>输出样例2</strong></h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line"><span class="number">2</span>/<span class="number">1</span></span><br></pre></td></tr></table></figure><h2 id="注"><strong>注</strong></h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line">__gcd(a, b);是求a和b的最大公因数的函数.</span><br></pre></td></tr></table></figure><h2 id="解答-189"><strong>解答</strong></h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br><span class="line">24</span><br><span class="line">25</span><br><span class="line">26</span><br><span class="line">27</span><br><span class="line">28</span><br></pre></td><td class="code"><pre><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><iostream></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><cstring></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><algorithm></span></span></span><br><span class="line"></span><br><span class="line"><span class="keyword">using</span> <span class="keyword">namespace</span> std;</span><br><span class="line"></span><br><span class="line"><span class="function"><span class="type">int</span> <span class="title">getSum</span><span class="params">(<span class="type">int</span> x,<span class="type">int</span> k)</span></span>{</span><br><span class="line"> <span class="type">int</span> sum=<span class="number">0</span>;</span><br><span class="line"> <span class="keyword">while</span>(x){</span><br><span class="line"> sum+=x%k;</span><br><span class="line"> x/=k;</span><br><span class="line"> }</span><br><span class="line"> <span class="keyword">return</span> sum;</span><br><span class="line">}</span><br><span class="line"></span><br><span class="line"><span class="function"><span class="type">int</span> <span class="title">main</span><span class="params">()</span></span></span><br><span class="line"><span class="function"></span>{</span><br><span class="line"> <span class="type">int</span> x;</span><br><span class="line"> <span class="built_in">scanf</span>(<span class="string">"%d"</span>, &x);</span><br><span class="line"> </span><br><span class="line"> <span class="type">int</span> sum=<span class="number">0</span>;</span><br><span class="line"> <span class="keyword">for</span>(<span class="type">int</span> i=<span class="number">2</span>;i<=x<span class="number">-1</span>;i++){</span><br><span class="line"> sum+=<span class="built_in">getSum</span>(x,i);</span><br><span class="line"> }</span><br><span class="line"> </span><br><span class="line"> <span class="type">int</span> num=__gcd(sum, x<span class="number">-2</span>);</span><br><span class="line"> <span class="built_in">printf</span>(<span class="string">"%d/%d"</span>,sum/num,(x<span class="number">-2</span>)/num);</span><br><span class="line">}</span><br></pre></td></tr></table></figure>]]></content>
<summary type="html"><h2 id="题目-169"><strong>题目</strong></h2>
<p>给定一个大于 2 的十进制正整数 A。</p>
<p>该数字在 2∼A−1 进制表示下的各位数字之和均可以求出。</p>
<p>例如，数字 123 在 16 进制表示下，共有 2 位：第 1 </summary>
<category term="算法" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/"/>
<category term="Acwing" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/Acwing/"/>
<category term="Acwing周赛" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/Acwing/Acwing%E5%91%A8%E8%B5%9B/"/>
</entry>
<entry>
<title>4209-三元组</title>
<link href="http://example.com/2022/07/16/algorithm/Acwing/WeeklyMatches/WeeklyMatches34/4209_%E4%B8%89%E5%85%83%E7%BB%84/"/>
<id>http://example.com/2022/07/16/algorithm/Acwing/WeeklyMatches/WeeklyMatches34/4209_%E4%B8%89%E5%85%83%E7%BB%84/</id>
<published>2022-07-16T03:25:18.889Z</published>
<updated>2022-07-16T12:26:13.838Z</updated>
<content type="html"><![CDATA[<h2 id="题目-168"><strong>题目</strong></h2><p>给定 n 个整数三元组 (xi,yi,zi)。</p><p>请你判断这些整数三元组是否能够同时满足以下三个条件：</p><ul><li>所有 xi 相加之和为 0。</li><li>所有 yi 相加之和为 0。</li><li>所有 zi 相加之和为 0。</li></ul><h2 id="输入格式-156"><strong>输入格式</strong></h2><p>第一行包含整数 n。</p><p>接下来 n 行，每行包含三个整数 xi,yi,zi。</p><h2 id="输出格式-156"><strong>输出格式</strong></h2><p>如果能够同时满足三个条件，则输出 YES，否则输出 NO。</p><h2 id="数据范围-182"><strong>数据范围</strong></h2><p>前三个测试点满足 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mn>1</mn><mo>≤</mo><mi>n</mi><mo>≤</mo><mn>10</mn></mrow><annotation encoding="application/x-tex">1≤n≤10</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.7804em;vertical-align:-0.136em;"></span><span class="mord">1</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.7719em;vertical-align:-0.136em;"></span><span class="mord mathnormal">n</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.6444em;"></span><span class="mord">10</span></span></span></span>。<br>所有测试点满足 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mn>1</mn><mo>≤</mo><mi>n</mi><mo>≤</mo><mn>100</mn><mtext>，</mtext><mo>−</mo><mn>100</mn><mo>≤</mo><msub><mi>x</mi><mi>i</mi></msub><mo separator="true">,</mo><msub><mi>y</mi><mi>i</mi></msub><mo separator="true">,</mo><msub><mi>z</mi><mi>i</mi></msub><mo>≤</mo><mn>100</mn><mtext>。</mtext></mrow><annotation encoding="application/x-tex">1≤n≤100，−100≤x_i,y_i,z_i≤100。</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.7804em;vertical-align:-0.136em;"></span><span class="mord">1</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.7719em;vertical-align:-0.136em;"></span><span class="mord mathnormal">n</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.7667em;vertical-align:-0.0833em;"></span><span class="mord">100</span><span class="mord cjk_fallback">，</span><span class="mspace" style="margin-right:0.2222em;"></span><span class="mbin">−</span><span class="mspace" style="margin-right:0.2222em;"></span></span><span class="base"><span class="strut" style="height:0.7804em;vertical-align:-0.136em;"></span><span class="mord">100</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.8304em;vertical-align:-0.1944em;"></span><span class="mord"><span class="mord mathnormal">x</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">i</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord mathnormal" style="margin-right:0.03588em;">y</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:-0.0359em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">i</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord mathnormal" style="margin-right:0.04398em;">z</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:-0.044em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">i</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">≤</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.6833em;"></span><span class="mord">100</span><span class="mord cjk_fallback">。</span></span></span></span></p><h2 id="输入样例1"><strong>输入样例1</strong></h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br></pre></td><td class="code"><pre><span class="line"><span class="number">4</span></span><br><span class="line"><span class="number">3</span> <span class="number">-1</span> <span class="number">7</span></span><br><span class="line"><span class="number">-5</span> <span class="number">2</span> <span class="number">-4</span></span><br><span class="line"><span class="number">0</span> <span class="number">-2</span> <span class="number">-1</span></span><br><span class="line"><span class="number">2</span> <span class="number">1</span> <span class="number">-2</span></span><br></pre></td></tr></table></figure><h2 id="输出样例1"><strong>输出样例1</strong></h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line">YES</span><br></pre></td></tr></table></figure><h2 id="输入样例2"><strong>输入样例2</strong></h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br></pre></td><td class="code"><pre><span class="line"><span class="number">3</span></span><br><span class="line"><span class="number">4</span> <span class="number">1</span> <span class="number">7</span></span><br><span class="line"><span class="number">-2</span> <span class="number">4</span> <span class="number">-1</span></span><br><span class="line"><span class="number">1</span> <span class="number">-5</span> <span class="number">-3</span></span><br></pre></td></tr></table></figure><h2 id="输出样例2"><strong>输出样例2</strong></h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line">NO</span><br></pre></td></tr></table></figure><h2 id="解答-188"><strong>解答</strong></h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br><span class="line">24</span><br><span class="line">25</span><br><span class="line">26</span><br></pre></td><td class="code"><pre><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><iostream></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><cstring></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><algorithm></span></span></span><br><span class="line"></span><br><span class="line"><span class="keyword">using</span> <span class="keyword">namespace</span> std;</span><br><span class="line"></span><br><span class="line"><span class="type">int</span> xSum=<span class="number">0</span>,ySum=<span class="number">0</span>,zSum=<span class="number">0</span>;</span><br><span class="line"></span><br><span class="line"><span class="function"><span class="type">int</span> <span class="title">main</span><span class="params">()</span></span></span><br><span class="line"><span class="function"></span>{</span><br><span class="line"> <span class="type">int</span> n;</span><br><span class="line"> <span class="built_in">scanf</span>(<span class="string">"%d"</span>, &n);</span><br><span class="line"> </span><br><span class="line"> <span class="type">int</span> x,y,z;</span><br><span class="line"> <span class="keyword">for</span> (<span class="type">int</span> i = <span class="number">0</span>; i < n; i ++ ){</span><br><span class="line"> <span class="built_in">scanf</span>(<span class="string">"%d%d%d"</span>, &x,&y,&z);</span><br><span class="line"> xSum+=x,ySum+=y,zSum+=z;</span><br><span class="line"> }</span><br><span class="line"> </span><br><span class="line"> <span class="keyword">if</span>(xSum==<span class="number">0</span>&&ySum==<span class="number">0</span>&&zSum==<span class="number">0</span>)</span><br><span class="line"> <span class="built_in">printf</span>(<span class="string">"YES"</span>);</span><br><span class="line"> <span class="keyword">else</span></span><br><span class="line"> <span class="built_in">printf</span>(<span class="string">"NO"</span>);</span><br><span class="line"> </span><br><span class="line"> <span class="keyword">return</span> <span class="number">0</span>;</span><br><span class="line">}</span><br></pre></td></tr></table></figure>]]></content>
<summary type="html"><h2 id="题目-168"><strong>题目</strong></h2>
<p>给定 n 个整数三元组 (xi,yi,zi)。</p>
<p>请你判断这些整数三元组是否能够同时满足以下三个条件：</p>
<ul>
<li>所有 xi 相加之和为 0。</li>
<li>所</summary>
<category term="算法" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/"/>
<category term="Acwing" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/Acwing/"/>
<category term="Acwing周赛" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/Acwing/Acwing%E5%91%A8%E8%B5%9B/"/>
</entry>
<entry>
<title>4208-电话号码</title>
<link href="http://example.com/2022/07/16/algorithm/Acwing/WeeklyMatches/WeeklyMatches33/4208_%E7%94%B5%E8%AF%9D%E5%8F%B7%E7%A0%81/"/>
<id>http://example.com/2022/07/16/algorithm/Acwing/WeeklyMatches/WeeklyMatches33/4208_%E7%94%B5%E8%AF%9D%E5%8F%B7%E7%A0%81/</id>
<published>2022-07-16T03:25:18.885Z</published>
<updated>2022-07-16T12:26:15.608Z</updated>
<content type="html"><![CDATA[<h2 id="题目-小声哔哔-跟阅读理解似的"><strong>题目(小声哔哔:跟阅读理解似的)</strong></h2><p>一个电话销售员正在整理他的电话簿。</p><p>电话簿中记录了他的全部客户的电话号码。</p><p>一个客户可能有不止一个电话号码。</p><p>不同客户可能拥有完全相同的电话号码。</p><p>电话簿中一共包含 n 条记录。</p><p>每条记录都是首先包含一个字符串，表示客户的姓名，然后包含一个整数，表示本条记录包含的电话号码数量，最后是本条记录所包含的电话号码。</p><p>不同客户的姓名两两不同，所以如果两条记录包含的客户姓名相同，那么我们认为这都是记录的同一人的电话信息。</p><p>同一记录中可能包含相同的电话号码，不同记录中也可能包含相同的电话号码。</p><p>在进行整理时，应遵守如下原则：</p><ul><li>如果一个客户拥有多条记录，则需要将这些记录进行合并，每人只保留一条记录，去记录他的全部有效号码。</li><li>如- 果一个客户记录的多个电话号码完全相同，则只保留一个作为有效号码，其余的全部视为无效号码。</li><li>如果一个客户记录的两个不同电话号码 a 和 b 满足 a 是 b 的后缀，则号码 a 视为无效号码。</li><li>请输出整理后的电话记录。</li></ul><h2 id="输入格式-161"><strong>输入格式</strong></h2><p>第一行包含整数 n，表示记录数量。</p><p>接下来 n 行，每行描述一条记录，首先包含一个长度不超过 10 的由小写字母构成的非空字符串，表示客户姓名，然后包含一个不超过 10 的正整数，表示本条记录包含的号码数量，最后包含本条记录的所有号码，每个号码都是长度不超过 10 的由数字构成的非空字符串，可能包含前导 0。</p><h2 id="输出格式-161"><strong>输出格式</strong></h2><p>首先输出一个整数 m，表示完成整理后的记录数量。</p><p>接下来 m 行，每行输出一条记录信息，格式要求与输入一致。</p><p>同一行的数据之间用单个空格隔开。</p><p>记录的先后顺序随意，一条记录中的号码顺序随意。</p><h2 id="数据范围-187"><strong>数据范围</strong></h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br></pre></td><td class="code"><pre><span class="line">前三个测试点满足 <span class="number">1</span>≤n≤<span class="number">4</span>。</span><br><span class="line">所有测试点满足 <span class="number">1</span>≤n≤<span class="number">20</span>。</span><br></pre></td></tr></table></figure><h2 id="输入样例1-6"><strong>输入样例1</strong></h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br></pre></td><td class="code"><pre><span class="line"><span class="number">2</span></span><br><span class="line">i <span class="number">1</span> <span class="number">00123</span></span><br><span class="line">m <span class="number">1</span> <span class="number">00123</span></span><br></pre></td></tr></table></figure><h2 id="输出样例1-6"><strong>输出样例1</strong></h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br></pre></td><td class="code"><pre><span class="line"><span class="number">2</span></span><br><span class="line">m <span class="number">1</span> <span class="number">00123</span> </span><br><span class="line">i <span class="number">1</span> <span class="number">00123</span></span><br></pre></td></tr></table></figure><h2 id="输入样例2-6"><strong>输入样例2</strong></h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br></pre></td><td class="code"><pre><span class="line"><span class="number">3</span></span><br><span class="line">l <span class="number">2</span> <span class="number">612</span> <span class="number">12</span></span><br><span class="line">p <span class="number">1</span> <span class="number">12</span></span><br><span class="line">k <span class="number">1</span> <span class="number">612</span></span><br></pre></td></tr></table></figure><h2 id="输出样例2-6"><strong>输出样例2</strong></h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br></pre></td><td class="code"><pre><span class="line"><span class="number">3</span></span><br><span class="line">k <span class="number">1</span> <span class="number">612</span> </span><br><span class="line">p <span class="number">1</span> <span class="number">12</span> </span><br><span class="line">l <span class="number">1</span> <span class="number">612</span></span><br></pre></td></tr></table></figure><h2 id="输入样例3-2"><strong>输入样例3</strong></h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br></pre></td><td class="code"><pre><span class="line"><span class="number">4</span></span><br><span class="line">i <span class="number">3</span> <span class="number">123</span> <span class="number">123</span> <span class="number">456</span></span><br><span class="line">i <span class="number">2</span> <span class="number">456</span> <span class="number">456</span></span><br><span class="line">i <span class="number">8</span> <span class="number">789</span> <span class="number">3</span> <span class="number">23</span> <span class="number">6</span> <span class="number">56</span> <span class="number">9</span> <span class="number">89</span> <span class="number">2</span></span><br><span class="line">d <span class="number">2</span> <span class="number">23</span> <span class="number">789</span></span><br></pre></td></tr></table></figure><h2 id="输出样例3-2"><strong>输出样例3</strong></h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br></pre></td><td class="code"><pre><span class="line"><span class="number">2</span></span><br><span class="line">d <span class="number">2</span> <span class="number">23</span> <span class="number">789</span> </span><br><span class="line">i <span class="number">4</span> <span class="number">789</span> <span class="number">123</span> <span class="number">2</span> <span class="number">456</span> </span><br></pre></td></tr></table></figure><h2 id="解答-190"><strong>解答</strong></h2><figure class="highlight c++"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br><span class="line">24</span><br><span class="line">25</span><br><span class="line">26</span><br><span class="line">27</span><br><span class="line">28</span><br><span class="line">29</span><br><span class="line">30</span><br><span class="line">31</span><br><span class="line">32</span><br><span class="line">33</span><br><span class="line">34</span><br><span class="line">35</span><br><span class="line">36</span><br><span class="line">37</span><br><span class="line">38</span><br><span class="line">39</span><br><span class="line">40</span><br><span class="line">41</span><br><span class="line">42</span><br><span class="line">43</span><br><span class="line">44</span><br><span class="line">45</span><br><span class="line">46</span><br><span class="line">47</span><br><span class="line">48</span><br></pre></td><td class="code"><pre><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><iostream></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><cstring></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><algorithm></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><map></span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string"><vector></span></span></span><br><span class="line"><span class="keyword">using</span> <span class="keyword">namespace</span> std;</span><br><span class="line"></span><br><span class="line">map<string, vector<string>> g; <span class="comment">//用户名单</span></span><br><span class="line"></span><br><span class="line"><span class="function"><span class="type">void</span> <span class="title">check</span><span class="params">(vector<string> &v, string s)</span><span class="comment">//判断新的电话是否合法</span></span></span><br><span class="line"><span class="function"></span>{</span><br><span class="line"> <span class="keyword">for</span>(<span class="keyword">auto</span> &x: v)</span><br><span class="line"> <span class="keyword">if</span>(x == s || x.<span class="built_in">find</span>(s, x.<span class="built_in">size</span>() - s.<span class="built_in">size</span>()) != string::npos) <span class="keyword">return</span>;</span><br><span class="line"> <span class="comment">//如果新的号码已存在，或者新的号码是合法号码中某一个的后缀，则不加入。</span></span><br><span class="line"> <span class="keyword">else</span> <span class="keyword">if</span>(s.<span class="built_in">find</span>(x, s.<span class="built_in">size</span>() - x.<span class="built_in">size</span>()) != string::npos)</span><br><span class="line"> <span class="comment">//如果合法号码中有号码是新的号码的后缀，那么用新的号码替换他。</span></span><br><span class="line"> {</span><br><span class="line"> x = s;</span><br><span class="line"> <span class="keyword">return</span>;</span><br><span class="line"> }</span><br><span class="line"> v.<span class="built_in">push_back</span>(s);<span class="comment">//合法，加入</span></span><br><span class="line">}</span><br><span class="line"></span><br><span class="line"><span class="function"><span class="type">int</span> <span class="title">main</span><span class="params">()</span></span></span><br><span class="line"><span class="function"></span>{</span><br><span class="line"> <span class="type">int</span> n, t;</span><br><span class="line"> cin >> n;</span><br><span class="line"> string name, num;</span><br><span class="line"> <span class="keyword">while</span> (n -- )</span><br><span class="line"> {</span><br><span class="line"> cin >> name >> t;</span><br><span class="line"> <span class="keyword">while</span>(t -- )</span><br><span class="line"> {</span><br><span class="line"> cin >> num;</span><br><span class="line"> <span class="built_in">check</span>(g[name], num);</span><br><span class="line"> }</span><br><span class="line"> }</span><br><span class="line"></span><br><span class="line"> cout << g.<span class="built_in">size</span>() << endl;</span><br><span class="line"> <span class="keyword">for</span>(<span class="keyword">auto</span> &x : g)</span><br><span class="line"> {</span><br><span class="line"> cout << x.first << <span class="string">' '</span> << x.second.<span class="built_in">size</span>() << <span class="string">' '</span>;</span><br><span class="line"> <span class="keyword">for</span>(<span class="keyword">auto</span> &s : x.second)</span><br><span class="line"> cout << s << <span class="string">' '</span>;</span><br><span class="line"> cout << endl;</span><br><span class="line"> }</span><br><span class="line"> <span class="keyword">return</span> <span class="number">0</span>;</span><br><span class="line">}</span><br></pre></td></tr></table></figure>]]></content>
<summary type="html"><h2 id="题目-小声哔哔-跟阅读理解似的"><strong>题目(小声哔哔:跟阅读理解似的)</strong></h2>
<p>一个电话销售员正在整理他的电话簿。</p>
<p>电话簿中记录了他的全部客户的电话号码。</p>
<p>一个客户可能有不止一个电话号码。</p>
</summary>
<category term="算法" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/"/>
<category term="Acwing" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/Acwing/"/>
<category term="Acwing周赛" scheme="http://example.com/categories/%E7%AE%97%E6%B3%95/Acwing/Acwing%E5%91%A8%E8%B5%9B/"/>
</entry>
</feed>