剑指offer60-把二叉树打印成多行**

# -*- coding:utf-8 -*-
# class TreeNode:
#     def __init__(self, x):
#         self.val = x
#         self.left = None
#         self.right = None
class Solution:
    def Print(self, pRoot):
        # write code here
        if pRoot is None:
            return []
        cur_depth=[pRoot]            #当前层
        next_depth=[]                #下一层
        rlt=[]
        while cur_depth:
            for i in cur_depth:
                if i.left:
                    next_depth.append(i.left)
                if i.right:
                    next_depth.append(i.right)
            rlt.append([i.val for i in cur_depth])    #要存入数组的是当前层节点的值，注意用法[func(i) for i in list]
            cur_depth,next_depth=next_depth,[]
        return rlt