#!/usr/bin/env python

# -*- coding:UTF-8

import copy

__author__ = 'shenshijun'

class Stack(object):

"""

使用Python快速实现一个栈

"""

def __init__(self, *arg):

super(Stack, self).__init__()

self.__stack = list(copy.copy(arg))

self.__size = len(self.__stack)

def push(self, value):

self.__stack.append(value)

self.__size += 1

def pop(self):

if self.__size <= 0:

return None

else:

value = self.__stack[-1]

self.__size -= 1

del self.__stack[-1]

return value

def __len__(self):

return self.__size

def empty(self):

return self.__size <= 0

def __str__(self):

return "".join(["Stack(list=", str(map(lambda s: str(s), self.__stack)), ",size=", str(self.__size), ')'])