# !/usr/bin/env python

# -*- coding: utf-8 -*-

__author__ = 'MrHero'

class SqStack(object):

"""

栈的线性结构

"""

def __init__(self, size):

self.data = list(None for _ in range(size))

self.max_size = size

self.top = -1

def get_length(self):

# 返回栈的长度

return self.top + 1

def push(self, elem):

# 进栈

if self.top + 1 == self.max_size:

raise IndexError("Stack is full")

else:

self.top += 1

self.data[self.top] = elem

def pop(self):

# 出栈

if self.top == -1:

raise IndexError("Stack is empty")

else:

self.top -= 1

return self.data[self.top + 1]

def get_top(self):

# 取栈顶元素

if self.top == -1:

raise IndexError("Stack is empty")

else:

return self.data[self.top]

def show_stack(self):

# 从栈顶向下开始显示栈里面的元素

j = self.top

while j >= 0:

print self.data[j]

j -= 1

def is_empty_stack(self):

return self.top == -1

if __name__ == '__main__':

sqs = SqStack(5)

sqs.push(1)

sqs.push(2)

sqs.push(3)

sqs.show_stack()