购物车程序：
1、启动程序后，输入用户名密码后，如果是第一次登录，让用户输入工资，然后打印商品列表
2、允许用户根据商品编号购买商品
3、用户选择商品后，检测余额是否够，够就直接扣款，不够就提醒
4、可随时退出，退出时，打印已购买商品和余额
5、在用户使用过程中， 关键输出，如余额，商品已加入购物车等消息，需高亮显示
6、用户下一次登录后，输入用户名密码，直接回到上次的状态，即上次消费的余额什么的还是那些，再次登录可继续购买
7、允许查询之前的消费记录
#! /usr/bin/env python
# -*- coding: utf-8 -*-
# __author__ = "Deakin"
# Email: 469792427@qq.com
# Date: 2018/1/17
product_list=[
["iphone",8000],
["computer",6000],
["car",30000],
["coffee",30],
["watch",500],
["book",80],
]
shopping_list=[]
file=open(‘user‘,‘r+‘,encoding=‘utf-8‘)
f=eval(file.read())
file1=open(‘history‘,‘r+‘,encoding=‘utf-8‘)
f1=eval(file1.read())
account=input("pls key in your account:")
while True:
if account in f:
password=input("pls key in your password:")
if password in f[account]:
salary=int(f[account][password])
print(‘welcome %s,your balance salary is %s‘%(account,salary))
print(‘-----below is your shopping car history-----‘)
if account in f1:
historylist=f1[account]
else:
historylist=[]
print(historylist)
while True:
select=input(‘do you want to buy sth now?yes or no:‘)
if select==‘yes‘:
while True:
for index,item in enumerate(product_list):
print(index,item)
userchoice = input("pls select the product number,press ‘q‘ to quit:")
if userchoice.isdigit():
userchoice=int(userchoice)
if userchoice<len(product_list) and userchoice>=0:
price=product_list[userchoice]
if price[1]<salary:
confirm=input(‘pls confirm your selection,yes or no:‘)
if confirm==‘yes‘:
shopping_list.append(price)
salary-=price[1]
print(‘add \033[31;1m%s\033[0m in your shopping_list,your \033[31;1mbalance salary is %s\033[0m‘%(price,salary))
f[account][password]=str(salary)
file.seek(0)
file.write(str(f))
file.tell()
elif confirm==‘no‘:
pass
else:
print(‘invalid option‘)
else:
print("you don‘t have enough money")
elif userchoice==‘q‘:
print("------shopping list------")
for p in shopping_list:
print(p)
f1[account]=shopping_list
file1.seek(0)
file1.write(str(f1))
print(‘your repeated salary is %s‘%(salary))
exit()
else:
print(‘option invalid‘)
elif select==‘no‘:
exit()
else:
print(‘invalid option‘)
else:
print("password is incorrect,pls try again")
else:
newpwdsal={}
password_new=input("account don‘t exist,pls set up your password to register:")
salary_new=input("first time to log in, pls key in your salary:")
sal_new=int(salary_new)
newpwdsal[password_new]=sal_new #工资对应新密码
f[account]=newpwdsal #用户名对应密码和工资的小字典
file.seek(0)
file.write(str(f))
file.tell()
