剑指offer(四十七)之平衡二叉树

题目描述

输入一棵二叉树，判断该二叉树是否是平衡二叉树。

代码：

public class Solution {
   public boolean IsBalanced_Solution(TreeNode root) {
        if (root == null)
            return true;

        if (Math.abs(getHeight(root.left) - getHeight(root.right)) > 1)
            return false;

        return IsBalanced_Solution(root.left) && IsBalanced_Solution(root.right);

    }

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

    private int max(int a, int b) {
        return (a > b) ? a : b;
    }
}