# class TreeNode:
# def __init__(self, x):
# self.val = x
# self.left = None
# self.right = None
#
# 代码中的类名、方法名、参数名已经指定,请勿修改,直接返回方法规定的值即可
#
#
# @param root TreeNode类
# @return int整型
#
class Solution:
def maxDepth(self , root: TreeNode) -> int:
# write code here
if not root:
return 0
return 1 + max(self.maxDepth(root.left),self.maxDepth(root.right))