python-leetcode面试题解之第103题二叉树的锯齿形层序遍历-题解.zip

# Definition for a binary tree node. # class TreeNode(object): # def __init__(self, x): # self.val = x # self.left = None # self.right = None class Solution(object): def zigzagLevelOrder(self, root): """ :type root: TreeNode :rtype: List[List[int]] """ # level order if root is None: return [] q = [[root]] for level in q: record = [] for node in level: if node.left: record.append(node.left) if node.right: record.append(node.right) if record: q.append(record) # zigzag order res = [] for index, level in enumerate(q): temp = [x.val for x in level] if index % 2 == 0: res.append(temp) else: res.append(temp[::-1]) return res