题解 | #求二叉树的层序遍历#python 11行代码

class Solution:
    def levelOrder(self , root ):
        # write code here
        if not root:return []
        queue = [root] 
        res = []
        while queue:
            res.append([node.val for node in queue])
            temp = []
            for node in queue:
                if node.left:temp.append(node.left)
                if node.right:temp.append(node.right)
            queue = temp
        return res