题目描述
思路
LeetCode104. 二叉树的最大深度 变种
方法一：后序遍历(递归、dfs)
/**
* Definition for a binary tree node.
* public class TreeNode {
* int val;
* TreeNode left;
* TreeNode right;
* TreeNode() {}
* TreeNode(int val) { this.val = val; }
* TreeNode(int val, TreeNode left, TreeNode right) {
* this.val = val;
* this.left = left;
* this.right = right;
* }
* }
*/
class Solution {
private boolean isbalancedTree = true;
public boolean isBalanced(TreeNode root) {
depth(root);
return isbalancedTree;
}
// 求当前节点的高度
private int depth(TreeNode node) {
if (node == null) return 0;
int left = depth(node.left);
int right = depth(node.right);
if (Math.abs(left - right) > 1) isbalancedTree = false;
return Math.max(left, right) + 1;
}
}