Java [Leetcode 110]Balanced 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 of every node never differ by more than 1.

解题思路：

递归法解题。

代码如下：

/**
* Definition for a binary tree node.
* public class TreeNode {
*     int val;
*     TreeNode left;
*     TreeNode right;
*     TreeNode(int x) { val = x; }
* }
*/
public class Solution {
public boolean isBalanced(TreeNode root) {
if(root == null)
return true;
else{
if(Math.abs(getHeight(root.left) - getHeight(root.right)) > 1)
return false;
else
return isBalanced(root.left) && isBalanced(root.right);
}
}

public int getHeight(TreeNode root){
if(root == null)
return 0;
else return 1 + Math.max(getHeight(root.left), getHeight(root.right));
}
}