# -*- coding:utf-8 -*-
# class TreeNode:
# def __init__(self, x):
# self.val = x
# self.left = None
# self.right = None
class Solution:
# 返回从上到下每个节点值列表,例:[1,2,3]
def PrintFromTopToBottom(self, root):
# write code here
if not root:
return []
else:
currentStack1 = [root]
res = []
while currentStack1:
nextStack = []
for i in currentStack1:
if i.left : nextStack.append(i.left)
if i.right : nextStack.append(i.right)
res.append(i.val)
currentStack1 = nextStack
return res