练习

#!/usr/bin/env python
import sys

my_age=28
count = 0

def num(nums):    
    global count
    while count < 3:

        user_input = int(input("input your guess num:"))
        if user_input == my_age:
            print 'successful. you go it!!!'
            sys.exit(0)
        elif user_input < my_age:
            print 'small'
        else:
            print 'bigger'
        count +=1
        if count >2:
            print 'sb'

if __name__ == '__main__':
    num('nums')

#!/usr/bin/ env python
# -*- coding: UTF-8 -*-

stack = []

def pushit():
    stack.append(raw_input('enter new string:    '))

def popit():
    if len(stack)==0:
        print 'cannot pop from an empty stack!'
    else:
        print 'Removed [', stack.pop(),']'

def viewstack():
    print str(stack)

def showmenu():
    prompt ="""

p(U)sh
p(o)p
(v)iew
(q)uit

Enter choice:"""
    while True:
        while True:
            try:
                choice=raw_input(prompt).strip()[0].lower()
            except (IndexError, EOFError, KeyboardInterrupt):
                choice='q'
            print 'n\you picked: [%s]' %choice
            if choice not in 'uovq':
                print 'invalid option, try again'
            else:
                break

        if choice == 'q': break
        if choice =='u': pushit()
        if choice =='o': popit()
        if choice =='v': viewstack()

if __name__=='__main__':
    showmenu()