[Leetcode]@python 104. Maximum Depth of Binary Tree

题目链接

https://leetcode.com/problems/maximum-depth-of-binary-tree/

题目原文

Given a binary tree, find its maximum depth.

The maximum depth is the number of nodes along the longest path from the root node down to the farthest leaf node.

题目大意

给定一棵二叉树，返回这棵二叉树的深度

解题思路

使用递归，树的深度 = max（左子树深度，右子树深度）+ 1

代码

# Definition for a binary tree node.
# class TreeNode(object):
#     def __init__(self, x):
#         self.val = x
#         self.left = None
#         self.right = None

class Solution(object):
    def maxDepth(self, root):
        """
        :type root: TreeNode
        :rtype: int
        """
        if root == None:
            return 0
        else:
            return max(self.maxDepth(root.left) + 1, self.maxDepth(root.right) + 1)