Daily commits

Author: aucker

Diff for: daily/25-Jan12.cc

@@ -0,0 +1,31 @@
+#include <vector>
+using namespace std;
+
+class Solution {
+ public:
+  /**
+   * @brief LC2275: Largest Combinations w/ Bitwise AND GT 0
+   * Time: O(n logU), n: len(candidate), U = max(candidate)
+   * Space: O(1)
+   *
+   * @param candidates
+   * @return int
+   */
+  int largestCombination(vector<int>& candidates) {
+    int m = 0;
+    int max_val = *max_element(candidates.begin(), candidates.end());
+    while (max_val > 0) {
+      max_val >>= 1;
+      m++;
+    }
+    int ans = 0;
+    for (int i = 0; i < m; i++) {
+      int cnt = 0;
+      for (int x : candidates) {
+        cnt += x >> i & 1;
+      }
+      ans = max(ans, cnt);
+    }
+    return ans;
+  }
+};

Diff for: daily/25-Jan16.cc

@@ -0,0 +1,55 @@
+#include <vector>
+using namespace std;
+
+class Solution {
+ public:
+  /**
+   * @brief LC 3095: Shortest subarray w/ OR at least K
+   * Time: O(N), Space: O(1)
+   *
+   * @param nums
+   * @param k
+   * @return int
+   */
+  int minimumSubarrayLength(vector<int>& nums, int k) {
+    int ans = INT_MAX, left = 0, bottom = 0, right_or = 0;
+    for (int right = 0; right < nums.size(); right++) {
+      right_or |= nums[right];
+      while (left <= right && (nums[left] | right_or) >= k) {
+        ans = min(ans, right - left + 1);
+        left++;
+        if (bottom < left) {
+          for (int i = right - 1; i >= left; i--) {
+            nums[i] |= nums[i + 1];
+          }
+          bottom = right;
+          right_or = 0;
+        }
+      }
+    }
+    return ans == INT_MAX ? -1 : ans;
+  }
+
+  /**
+   * @brief LogTrick
+   * Time: O(n * logU), Space: O(1)
+   *
+   * @param nums
+   * @param k
+   * @return int
+   */
+  int minimumSubarrayLength1(vector<int>& nums, int k) {
+    int ans = INT_MAX;
+    for (int i = 0; i < nums.size(); i++) {
+      int x = nums[i];
+      if (x >= k) return 1;
+      for (int j = i - 1; j >= 0 && (nums[j] | x) != nums[j]; j--) {
+        nums[j] |= x;
+        if (nums[j] >= k) {
+          ans = min(ans, i - j + 1);
+        }
+      }
+    }
+    return ans == INT_MAX ? -1 : ans;
+  }
+};

Diff for: daily/25-Jan20.cc

@@ -0,0 +1,25 @@
+#include <vector>
+using namespace std;
+
+class Solution {
+ public:
+  /**
+   * @brief LC2239: find closest num to zero [E]
+   * Time: O(N), Space: O(1)
+   *
+   * @param nums
+   * @return int
+   */
+  int findClosestNumber(vector<int>& nums) {
+    int ans = INT_MAX;
+    for (int num : nums) {
+      if (abs(num) < abs(ans)) {
+        ans = num;
+      }
+      if (abs(num) == abs(ans)) {
+        ans = max(ans, num);
+      }
+    }
+    return ans;
+  }
+};

Diff for: daily/25-Jan9.cc

@@ -0,0 +1,52 @@
+#include <string>
+using namespace std;
+
+class Solution {
+ public:
+  /**
+   * @brief LC3297: count substrings that can be rearranged to contain a string
+   * Time: O(N + |\Sigma|)
+   *
+   * @param word1
+   * @param word2
+   * @return long long
+   */
+  long long validSubstringCount(string word1, string word2) {
+    if (word1.length() < word2.length()) return 0;
+
+    int diff[26]{};  // word1 and word2 char diffs
+    for (char c : word2) {
+      diff[c - 'a']++;
+    }
+
+    // count how many alphabet chars that less than word2 in window
+    int less = 0;
+    for (int d : diff) {
+      if (d > 0) {
+        less++;
+      }
+    }
+
+    long long ans = 0;
+    int left = 0;
+    for (char c : word1) {
+      diff[c - 'a']--;
+      if (diff[c - 'a'] == 0) {
+        // move c to window, occur of c same as word2
+        less--;
+      }
+      while (less == 0) {                     // window is right
+        char out_char = word1[left++] - 'a';  // to move out of window
+        if (diff[out_char] == 0) {
+          // before out_char move out of window, check occur
+          // if out_char in window is same as word2 occur
+          // when out_char move out of window, out_char in window lt word2
+          less++;
+        }
+        diff[out_char]++;
+      }
+      ans += left;
+    }
+    return ans;
+  }
+};