Time: 173 ms (26.58%), Space: 63.3 MB (24.22%) - LeetHub

Author: JanaSabuj

balance-a-binary-search-tree/balance-a-binary-search-tree.cpp

@@ -0,0 +1,40 @@
+/**
+ * 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) {}
+ * };
+ */
+typedef TreeNode node;
+class Solution {
+public:
+    vector<int> arr;
+    void inorder(node* root) {
+        if(root == NULL)
+            return;
+        inorder(root->left);
+        arr.push_back(root->val);
+        inorder(root->right);
+    }
+    
+    node* go(int low, int high) {
+        if(low > high)
+            return NULL;
+        
+        int mid = (low + high) / 2;
+        node* root = new node(arr[mid]);
+        root->left = go(low, mid - 1);
+        root->right = go(mid + 1, high);
+        return root;
+    }
+    
+    TreeNode* balanceBST(TreeNode* root) {
+        inorder(root);
+        int low = 0, high = arr.size() - 1;
+        return go(low, high);
+    }
+};