LeetCode Online Judge 题目C# 练习 - 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 everynode never differ by more than 1.

public static bool BalancedBinaryTree(BTNode root)
{
if (root == null)
return true;

if(Math.Abs(GetDepth(root.Left) - GetDepth(root.Right)) >= 2)
return false;
else
return BalancedBinaryTree(root.Left) && BalancedBinaryTree(root.Right);
}

public static int GetDepth(BTNode root)
{
if (root == null)
return 0;
if (root.Left == null && root.Right == null)
return 1;
else
return 1 + Math.Max(GetDepth(root.Left), GetDepth(root.Right));

代码分析：

　　看来是永无止境了，LeetCode上加了些Tree的题目，在做些吧，反正自己递归很弱。

　　上面是递归Top-down的做法，不知有没有bottom-up的做法，DP之类的。