牛客網上的劍指 offer的在線編程:
題目描述
# -*- 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 not pRoot: return []
res, tree, left_right = [], [pRoot], True
while tree:
sub_tree, row = [], []
for item in tree:
row.append(item.val)
if item.left:
sub_tree.append(item.left)
if item.right:
sub_tree.append(item.right)
if left_right:
res.append(row)
else:
row.reverse()
res.append(row)
tree = sub_tree
left_right = not left_right
return res