Python之路 day2 购物车小程序1

 #Author:ersa
 '''
 程序：购物车程序
 
 需求:
 
 启动程序后，让用户输入工资，然后打印商品列表
 允许用户根据商品编号购买商品
 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
 可随时退出，退出时，打印已购买商品和余额
 
 #知识点：len(market):列表长度（列表中的条目个数）
        isdigit() 判断输入的内容是否是数字，TRUE 是数字
        取列表数据 enumerate
        for index,item in enumerate(market)
             print(index, item)
     输出内容高亮显示 "\033[31;1m%s\033[0m"%(balance)
     退出程序使用exit()方法
 '''
 
 market = [[1,"iphone",5800],
           [2,"Mac Pro", 12000],
           [3,"Starbuck Latte",31],
           [4,"Alex Python",88],
           [5,"bike",1800]]
 
 balance = input("please input salary: ")
 if balance.isdigit():
     balance = int(balance)
 else:
     exit("Illegal value, please re-enter")
 
 amount = 0
 print("Tip: type q to exit.\n\n")
 
 shopping_cart = []
 while True:
     for commodity in market:
         print(commodity)
 
     user_choice = input("Please enter a product number or q：\n")
 
     if user_choice == "q":
         break
 
     if user_choice.isdigit():
         user_choice = int(user_choice)
         if 0 < user_choice and user_choice <= (len(market)+1):
             amount += market[user_choice - 1][2];
             if balance < amount:
                 print("Reminder: the balance is insufficient, please re-purchase.\n")
                 continue
             shopping_cart.append(market[user_choice - 1])
         else:
             print("If you do not have this item, please reselect it !\n")
             continue
 
 print("List of purchased items:\n")
 for commodity in shopping_cart:
     print(commodity)
 print("Payment amount: \033[41;1m%s\033[0m"%(amount))
 balance -= amount
 print("your balance: \033[31;1m%s\033[0m \n"%balance)