balcanced-binary-tree

题目描述

 

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 ofevery node never differ by more than 1.

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/**  * Definition for binary tree  * struct TreeNode {  *     int val;  *     TreeNode *left;  *     TreeNode *right;  *     TreeNode(int x) : val(x), left(NULL), right(NULL) {}  * };  */ class Solution { public:     int dept(TreeNode *root) {         if(root==NULL)  return 0;         if(root->left==NULL && root->right==NULL)             return 1;         return max(dept(root->left),dept(root->right))+1;     }           bool isBalanced(TreeNode *root) {         if(root==NULL)  return true;         int x=dept(root->left)-dept(root->right);         if(abs(x)>1)             return false;         else             return isBalanced(root->left) && isBalanced(root->right);     } };