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 ofevery node never differ by more than 1.

题目解析：

判断一棵树是不是平衡二叉数

1、他的左子树是平衡二叉树

2、他的右子树是平衡二叉树

3、他的左右子树的深度之差小于等于1

#include<iostream>using namespace std;struct TreeNode {    int val;    TreeNode *left;    TreeNode *right;    TreeNode(int x) : val(x), left(NULL), right(NULL) {}};int depthTree(TreeNode *root){if(root == NULL)return 0;return max(depthTree(root->left) + 1,depthTree(root->right) + 1);}bool isBalanced(TreeNode *root) {if(root == NULL)return true;if(isBalanced(root->left) && isBalanced(root->right) && abs( depthTree(root->left)-depthTree(root->right) )<=1 ){return true;}else{return false;}}int main(void){system("pause");return 0;}