0904 solved.

0904-Fruit-Into-Baskets/cpp-0904/CMakeLists.txt

@@ -0,0 +1,7 @@
+cmake_minimum_required(VERSION 3.5)
+project(B)
+
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")
+
+set(SOURCE_FILES main2.cpp)
+add_executable(B ${SOURCE_FILES})

0904-Fruit-Into-Baskets/cpp-0904/main.cpp

@@ -0,0 +1,65 @@
+/// Source : https://leetcode.com/problems/fruit-into-baskets/description/
+/// Author : liuyubobobo
+/// Time   : 2018-09-15
+
+#include <iostream>
+#include <vector>
+#include <unordered_set>
+
+using namespace std;
+
+
+/// Segment the array into blocks
+/// Time Complexity: O(n)
+/// Space Complexity: O(n)
+class Solution {
+public:
+    int totalFruit(vector<int>& tree) {
+
+        vector<pair<int, int>> blocks;
+        int start = 0;
+        for(int i = start + 1; i <= tree.size(); i ++)
+            if(i == tree.size() || tree[i] != tree[start]){
+                blocks.push_back(make_pair(tree[start], i - start));
+                start = i;
+                i = start;
+            }
+//        for(const pair<int, int>& p: blocks)
+//            cout << "(" << p.first << "," << p.second << ") ";
+//        cout << endl;
+
+        int res = 0;
+        unordered_set<int> fruits;
+        int sum = 0;
+        for(int i = 0; i <= blocks.size();)
+            if(i == blocks.size() || (fruits.size() == 2 && fruits.count(blocks[i].first) == 0)){
+                res = max(res, sum);
+
+                if(i < blocks.size()){
+                    sum = 0;
+                    i --;
+                    fruits.clear();
+                }
+                else
+                    break;
+            }
+            else{
+                fruits.insert(blocks[i].first);
+                sum += blocks[i].second;
+                i ++;
+            }
+        return res;
+    }
+};
+
+
+int main() {
+
+    vector<int> nums1 = {1, 2, 1};
+    cout << Solution().totalFruit(nums1) << endl;
+
+    vector<int> nums2 = {0, 1, 2, 2};
+    cout << Solution().totalFruit(nums2) << endl;
+
+    return 0;
+}

0904-Fruit-Into-Baskets/cpp-0904/main2.cpp

@@ -0,0 +1,52 @@
+/// Source : https://leetcode.com/problems/fruit-into-baskets/description/
+/// Author : liuyubobobo
+/// Time   : 2018-09-15
+
+#include <iostream>
+#include <vector>
+#include <unordered_map>
+
+using namespace std;
+
+
+/// Sliding Window
+/// Time Complexity: O(n)
+/// Space Complexity: O(1)
+class Solution {
+public:
+    int totalFruit(vector<int>& tree) {
+
+        unordered_map<int, int> freq;
+        int l = 0, r = -1, res = 0;
+        while(l < tree.size()){
+            if(freq.size() <= 2 && r + 1 < tree.size()){
+                r ++;
+                freq[tree[r]] ++;
+            }
+            else{
+                freq[tree[l]] --;
+                if(freq[tree[l]] == 0)
+                    freq.erase(tree[l]);
+                l ++;
+            }
+
+            if(freq.size() <= 2)
+                res = max(res, getFruits(freq));
+        }
+        return res;
+    }
+
+private:
+    int getFruits(const unordered_map<int, int>& freq){
+        int res = 0;
+        for(const pair<int, int>& p: freq)
+            res += p.second;
+        return res;
+    }
+};
+
+
+int main() {
+
+    return 0;
+}

readme.md

@@ -513,6 +513,6 @@ email: [[email protected]](mailto:[email protected])
 | 901 | [Online Stock Span](https://leetcode.com/problems/online-stock-span/description/) | [solution](https://leetcode.com/problems/online-stock-span/solution/) | [C++](0901-Online-Stock-Span/cpp-0901/) | | |
 | 902 | [Numbers At Most N Given Digit Set](https://leetcode.com/problems/numbers-at-most-n-given-digit-set/description/) | [solution](https://leetcode.com/problems/numbers-at-most-n-given-digit-set/solution/) | [C++](0902-Numbers-At-Most-N-Given-Digit-Set/cpp-0902/) | | |
 | 903 | [Valid Permutations for DI Sequence](https://leetcode.com/problems/valid-permutations-for-di-sequence/description/) | [solution](https://leetcode.com/problems/valid-permutations-for-di-sequence/solution/)<br/>[缺：O(n^2) DP] | [C++](0903-Valid-Permutations-for-DI-Sequence/cpp-0903/) | | |
-| | | | | | |
+| 904 | [Fruit Into Baskets](https://leetcode.com/problems/fruit-into-baskets/description/) | [solution](https://leetcode.com/problems/fruit-into-baskets/solution/) | [C++](0904-Fruit-Into-Baskets/cpp-0904/) | | |
 | 905 | [Sort Array By Parity](https://leetcode.com/problems/sort-array-by-parity/description/) | [solution](https://leetcode.com/problems/sort-array-by-parity/solution/) | [C++](0905-Sort-Array-By-Parity/cpp-0905/) | | |
 | | | | | | |