Leetcode 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.

Difficulty: Easy

/**
* Definition for a binary tree node.
* public class TreeNode {
* int val;
* TreeNode left;
* TreeNode right;
* TreeNode(int x) { val = x; }
* }
*/
public class Solution {
public int height(TreeNode root){
if(root == null) return 0;
int left = height(root.left);
int right = height(root.right);
if(left == -1 || right == -1 || Math.abs(left - right) > 1)
return -1;
return 1 + Math.max(left, right);
}
public boolean isBalanced(TreeNode root) {
if(root == null) return true;
int left = height(root.left);
int right = height(root.right);
if(left == -1 || right == -1 || Math.abs(left - right) > 1)
return false;
return true;
}
}