剑指offer--面试题61：按之字形顺序打印二叉树

题目描述

# -*- 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 pRoot is None:
            return []
        result = []
        tmpResult = []
        from collections import deque
        queue = deque([pRoot])
        curLevelNum = 1
        isEven = False
        while queue:
            while curLevelNum:
                front = queue.popleft()
                curLevelNum -= 1
                tmpResult.append(front.val)
                if front.left:
                    queue.append(front.left)
                if front.right:
                    queue.append(front.right)
            curLevelNum = len(queue)
            if isEven:
                result.append(tmpResult[::-1])
                isEven = False
            else:
                result.append(tmpResult[:])
                isEven = True
            tmpResult = []
        return result