题解 | #按之字形顺序打印二叉树#

# -*- 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
         # write code here
        result = []
        if not pRoot:
            return result
        level_nodes = [pRoot]
        rev = True
        while(level_nodes):
            new_level_nodes = []
            result.append([])
            for i in level_nodes:
                result[-1].append(i.val)
                if i.left:
                    new_level_nodes.append(i.left)
                if i.right:
                    new_level_nodes.append(i.right)
            level_nodes = new_level_nodes
            if not rev:
                result[-1] = result[-1][-1::-1]
            rev = not rev
        return result