1 """
2 自己AC
3 为了实现Z字形遍历
4 记录了二叉树的depth，如果depth为2的倍数
5 将得到的值reverse()处理一下再存入res中
6 """
7
8 class TreeNode:
9 def __init__(self, x):
10 self.val = x
11 self.left = None
12 self.right = None
13
14 class Solution:
15 def zigzagLevelOrder(self, root):
16 if not root:
17 return []
18 res = []
19 queue = []
20 queue.append(root)
21 depth = 1
22 while queue:
23 cur = []
24 for x in queue:
25 cur.append(x.val)
26 if depth % 2 == 0:#bug 写进for循环里了
27 cur.reverse()
28 res.append(cur)
29 newqueue = []
30 for x in queue:
31 if x.left:
32 newqueue.append(x.left)
33 if x.right:
34 newqueue.append(x.right)
35 queue = newqueue
36 depth += 1
37 return res
