LeetCode题解：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.

题意：判断左右子树高度差是否大于1

解决思路：……

代码：

public class Solution {
    public boolean isBalanced(TreeNode root) {
        if(root == null){
            return true;
        }

        if(Math.abs(depth(root.left) - depth(root.right)) > 1){
            return false;
        }

        return isBalanced(root.left) && isBalanced(root.right);
    }

    private int depth(TreeNode root){
        if(root == null){
            return 0;
        }

        return Math.max(depth(root.left), depth(root.right)) + 1;
    }
}