LeetCode-110.Balanced Binary Tree

https://leetcode.com/problems/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.

判断一棵树是否平衡，要分别判断其左右子树是否平衡

/**
* Definition for a binary tree node.
* public class TreeNode {
*     public int val;
*     public TreeNode left;
*     public TreeNode right;
*     public TreeNode(int x) { val = x; }
* }
*/
public class Solution
{
public bool IsBalanced(TreeNode root)
{
return Func(root) != -1;
}

private int Func(TreeNode root)
{
if (root == null)
return 0;
int left = Func(root.left);
int right = Func(root.right);
if (left == -1 || right == -1 || Math.Abs(left-right)>1)
return -1;
return Math.Max(left, right) + 1;
}
}