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
#
# 每一层仅计数
class Solution:
    def maxDepth(self , root: TreeNode) -> int:
        if not root:
            return 0
        
        cur = [root]
        nex = []
        count = 0

        while cur:
            for node in cur:
                if node.left:
                    nex.append(node.left)
                if node.right:
                    nex.append(node.right)
            cur = nex
            nex = []
            count += 1
        
        return count