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.

判断是否为平衡二叉树，递归算出某个节点深度，之后用于算深度类似的方法判断是否为平衡二叉树。

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