题目：
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.
思路：计算左右子树的深度是否超过1，用递归计算
代码：
/** * Definition for binary tree * public class TreeNode { * int val; * TreeNode left; * TreeNode right; * TreeNode(int x) { val = x; } * } */ public class Solution { boolean flag = false; public boolean isBalanced(TreeNode root) { getHeight(root); return !flag; } public int getHeight(TreeNode root) { if(flag || root == null) { return 0; } int left = getHeight(root.left)+1; int right = getHeight(root.right)+1; if(Math.abs(left-right) > 1) { flag = true; } return Math.max(left, right); } }