问题描述

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

解题思路

二叉树的最大深度，等于左子树的深度和右子树深度的较大值加1（即本层深度）.

代码

# Definition for a binary tree node.
# class TreeNode:
#     def __init__(self, val=0, left=None, right=None):
#         self.val = val
#         self.left = left
#         self.right = right
class Solution:
    def maxDepth(self, root: Optional[TreeNode]) -> int:
        if root is None:
            return 0
        return max(self.maxDepth(root.left), self.maxDepth(root.right))+1