题解 | #二叉树的最大深度#

# 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
#
from collections import deque
class Solution:
    def maxDepth(self , root: TreeNode) -> int:
        # write code here
        if root == None:
            return 0
        max = 0
        queue =deque()
        queue.append(root)

        while(len(queue)!=0):
           
            size  = len(queue)

            for i in range(size):
                curr = queue.popleft()
                if curr.left:
                    queue.append(curr.left)
                if curr.right:
                    queue.append(curr.right)
            max +=1
        
        return max

while循环的次数就是最大深度