Equal Tree Partition

Author: sachuverma

Leetcode Daily Challenge/August-2021/Equal Tree Partition.cpp

@@ -0,0 +1,72 @@
+/*
+Equal Tree Partition
+====================
+
+Given the root of a binary tree, return true if you can partition the tree into two trees with equal sums of values after removing exactly one edge on the original tree.
+
+Example 1:
+Input: root = [5,10,10,null,null,2,3]
+Output: true
+
+Example 2:
+Input: root = [1,2,10,null,null,2,20]
+Output: false
+Explanation: You cannot split the tree into two trees with equal sums after removing exactly one edge on the tree.
+
+Constraints:
+The number of nodes in the tree is in the range [1, 104].
+-105 <= Node.val <= 105
+*/
+
+/**
+ * Definition for a binary tree node.
+ * struct TreeNode {
+ *     int val;
+ *     TreeNode *left;
+ *     TreeNode *right;
+ *     TreeNode() : val(0), left(nullptr), right(nullptr) {}
+ *     TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}
+ *     TreeNode(int x, TreeNode *left, TreeNode *right) : val(x), left(left), right(right) {}
+ * };
+ */
+
+class Solution {
+public:
+    int dfs1(TreeNode* root) {
+        if(!root) return 0;
+        return root->val + dfs1(root->left) + dfs1(root->right);
+    }
+    
+    int dfs2(TreeNode* root, int& halfSum, bool& ans) {
+        int left = 0, right = 0;
+        if(root->left) {
+            left = dfs2(root->left, halfSum, ans);
+            if(left == halfSum) {
+                ans = true;
+                return 0;
+            }
+        }
+        
+        if(root->right) {
+            right = dfs2(root->right, halfSum, ans);
+            if(right == halfSum) {
+                ans = true;
+                return 0;
+            }
+        }
+        
+        return root->val + left + right;
+    }
+    
+    bool checkEqualTree(TreeNode* root) {
+        int fullSum = dfs1(root);
+        
+        if(fullSum % 2 != 0) return false;
+        int halfSum = fullSum / 2;
+        
+        bool ans = false;
+        dfs2(root, halfSum, ans);
+        
+        return ans;
+    }
+};

Leetcode Daily Challenge/August-2021/README.md

@@ -30,5 +30,5 @@
 | 26. | [Verify Preorder Serialization of a Binary Tree](https://leetcode.com/explore/challenge/card/august-leetcoding-challenge-2021/616/week-4-august-22nd-august-28th/3920/) | [cpp](./26.%20Verify%20Preorder%20Serialization%20of%20a%20Binary%20Tree.cpp) |
 | 27. | [Longest Uncommon Subsequence II](https://leetcode.com/explore/challenge/card/august-leetcoding-challenge-2021/616/week-4-august-22nd-august-28th/3921/) | [cpp](./27.%20Longest%20Uncommon%20Subsequence%20II.cpp) |
 | 28. | [Maximum Profit in Job Scheduling](https://leetcode.com/explore/challenge/card/august-leetcoding-challenge-2021/616/week-4-august-22nd-august-28th/3950/) | [cpp](./28.%20Maximum%20Profit%20in%20Job%20Scheduling.cpp) |
-| 28. | []() | [cpp](./28.%20.cpp) |
-| 28. | []() | [cpp](./28.%20.cpp) |
+|  | [Equal Tree Partition](https://leetcode.com/explore/challenge/card/august-leetcoding-challenge-2021/617/week-5-august-29th-august-31st/3955/) | [cpp](./Equal%20Tree%20Partition.cpp) |
+| 29. | []() | [cpp](./29.%20.cpp) |