题解 | #平衡二叉树#

递归记录树高以及是否为平衡二叉树。

# -*- coding:utf-8 -*-
# class TreeNode:
#     def __init__(self, x):
#         self.val = x
#         self.left = None
#         self.right = None
class Solution:
    def IsBalanced_Solution(self, pRoot):
        # write code here
        def dfs(root):
            if not root:
                return (0, True)
            lefth, left = dfs(root.left)
            righth, right = dfs(root.right)
            return (1+max(lefth, righth) ,left and right and abs(lefth-righth)<=1)
        return dfs(pRoot)[1]