【Leetcode】429—N-ary Tree Level O

一、题目描述

给定一个 N 叉树，返回其节点值的层序遍历。 (即从左到右，逐层遍历)。
例如，给定一个 3叉树 :

二、代码实现

"""
# Definition for a Node.
class Node(object):
    def __init__(self, val, children):
        self.val = val
        self.children = children
"""
class Solution(object):
    def levelOrder(self, root):
        """
        :type root: Node
        :rtype: List[List[int]]
        """
        if root == None: return []
        queue = [root]
        res = []
        while queue:
            layer = []
            for i in range(len(queue)):
                ele = queue.pop(0)
                layer.append(ele.val)
                if not ele.children: continue
                for child in ele.children: queue.append(child)
            res.append(layer)
        return res