0104：二叉树的最大深度

1
2
3
4
5
6
7

class Solution:
    def maxDepth(self, root: Optional[TreeNode]) -> int:
        res,Q = 0,[root] if root else []
        while Q:
            res += 1
            Q = [c for u in Q for c in [u.left,u.right] if c]
        return res