LeetCode110 Balanced Binary Tree

Given a binary tree, determine if it is height-balanced.

For this problem, a height-balanced binary tree is defined as a binary tree in which the depth of the two subtrees of every node never differ by more than 1.（Easy）

分析：

利用辅助函数求深度，然后根据heighted-balanced定义判定即可

代码：

 class Solution {
     int depth(TreeNode* root) {
         if (root == nullptr) {
             return ;
         }
         return max(depth(root -> left), depth(root -> right)) + ;
     }
 public:
     bool isBalanced(TreeNode* root) {
         if (root == nullptr) {
             return true;
         }
         int left = depth(root -> left);
         int right = depth(root -> right);
         if (abs(left - right) <=  && isBalanced(root -> left) && isBalanced(root -> right)) {
             return true;
         }
         return false;
     }
 };