LeetCode110.平衡二叉树

题目

 1 class Solution {
 2 public:
 3     bool isBalanced(TreeNode* root) {
 4         if(root == NULL) return true;
 5         return abs(height(root->left)-height(root->right)) <= 1 && isBalanced(root->left) && 
 6         isBalanced(root->right);
 7     }
 8     int height(TreeNode* root){
 9         if(root == NULL) return 0;
10         return max(height(root->left),height(root->right)) + 1;
11     }
12 };

一开始不会对每个结点进行高度判断，判断平衡的递归思想和镜像对称二叉树的那个题一个套路