#給一個(gè)點(diǎn)，我們能夠根據(jù)這個(gè)點(diǎn)知道一些內(nèi)容
class Node(object):
  def __init__(self): #定位的點(diǎn)的值和一個(gè)指向
    self.val=val  #指向元素的值,原隊(duì)列第二元素
    self.next=None  #指向的指針
class stack(object):
  def __init__(self):
    self.top=None #初始化最開(kāi)始的位置
  def peek(self): #獲取棧頂?shù)脑?
    if self.top!=None: #如果棧頂不為空
      return self.top.val #返回棧頂元素的值
    else:
      return None
  def push(self,n):#添加到棧中
    n=Node(n) #實(shí)例化節(jié)點(diǎn)
    n.next=self.top #頂端元素傳值給一個(gè)指針
    self.top=n  #
    return n.val
  def pop(self): #退出棧
    if self.top == None:
      return None
    else:
      tmp=self.top.val
      self.top=self.top.next #下移一位，進(jìn)行
      return tmp
if __name__=="__main__":
  s=stack()
  s.push(1)
  s.push(2)
  s.push(3)
  print s.pop()
  print s.pop()
  print s.pop()

3
2
1

#--coding: utf - 8--""
"
N = input("Please input a number::")
while (N):
  print "** @ **"
  N -= 1 ""
"
N = input("輸入十進(jìn)制數(shù)字（換算為八進(jìn)制）：：")
stack = []
string8 = ""
while (N):
  #求余
  stack.append(N % 8)# 求商
  N = N //8
while (len(stack) > 0):
  string8 += str(stack.pop())
print "轉(zhuǎn)換為八進(jìn)制：" + string8

#--coding: utf - 8--
class Stack(object):
  def __init__(self):
    self.items = []
  def isEmpty(self):
    return self.items == []
  def push(self, item):
    self.items.append(item)
  def pop(self):
    return self.items.pop()
  def GetTop(self):
    return
self.items[len(self.items) - 1]

#--coding: utf - 8--
import stack1
shiyan = stack1.Stack()
stringu = ""
temp = input("請(qǐng)輸入一個(gè)十進(jìn)制數(shù)字::")
while (temp):
  shiyan.push(temp % 8)
  temp = temp / 8
while (not shiyan.isEmpty()):
  stringu += str(shiyan.pop())
print "八進(jìn)制為：：" + stringu

#--coding:utf-8--
print "  ****括號(hào)匹配****  "
print """
輸入原則： 每當(dāng)你輸入一個(gè)括號(hào)， 你需要再輸入一個(gè)‘，'
進(jìn)行區(qū)分， 例如：(, [, ], (, ), )
輸入的可識(shí)別括號(hào)有(), [], {}
"""
strpp = raw_input("請(qǐng)輸入一段括號(hào)表達(dá)式：")
basestr = strpp.split(',')
pstack = []
suoyin = {'(': ')','[': ']','{': '}'}
for e in basestr:
  if (e == '(' or e == '[' or e == '}'):
    pstack.append(e)
  else :
    if len(pstack) == 0:
      print "右括號(hào)多余"
      break
    else :
      if e == suoyin[pstack[len(pstack) - 1]]:
        pstack.pop()
      else :
        print "不匹配"
        print "右括號(hào)多余"
        break
if len(pstack) == 0:
  print "匹配正確"
else :
  print "左括號(hào)多余"