# -*- coding:utf-8 -*-

class TreeNode:

def __init__(self, x):

self.val = x

self.left = None

self.right = None

class Solution:

def PrintByZigzag(self, pRoot):

# write code here

res, temp = [], []

if pRoot is None:

return res

temp = [pRoot]

right = True

while temp:

curstack,nextstack = [],[]

if right:

for node in temp:

curstack.append(node.val)

if node.left:

nextstack.append(node.left)

if node.right:

nextstack.append(node.right)

else:

for node in temp:

curstack.append(node.val)

if node.right:

nextstack.append(node.right)

if node.left:

nextstack.append(node.left)

nextstack.reverse()

temp = nextstack

right = not right

res.append(curstack)

return res

def PrintByZigzag2(self,pRoot):

res,temp = [],[]

if not pRoot:

return res

temp = [pRoot]

lefttoright = True

while temp:

cur, nextstack = [], []

for node in temp:

cur.append(node.val)

if node.left:

nextstack.append(node.left)

if node.right:

nextstack.append(node.right)

if not lefttoright:

cur.reverse()

res.append(cur)

temp = nextstack

lefttoright = not lefttoright

return res

def PrintToSeveralLevel(self, pRoot):

# write code here

res,temp = [],[]

if pRoot is None:

return res

temp = [pRoot]

while temp:

curstack, nextstack = [],[]

for node in temp:

curstack.append(node.val)

if node.left:

nextstack.append(node.left)

if node.right:

nextstack.append(node.right)

res.append(curstack)

temp = nextstack

return res

pNode1 = TreeNode(8)

pNode2 = TreeNode(6)

pNode3 = TreeNode(10)

pNode4 = TreeNode(5)

pNode5 = TreeNode(7)

pNode6 = TreeNode(9)

pNode7 = TreeNode(11)

pNode1.left = pNode2

pNode1.right = pNode3

pNode2.left = pNode4

pNode2.right = pNode5

pNode3.left = pNode6

pNode3.right = pNode7

S = Solution()

aList = S.PrintByZigzag2(pNode1)

print(aList)