1 while True:
2 salary = input("please input your salary:")
3 if salary.isdigit():
4 salary=int (salary)
5 break
6 else:
7 print("Invalid input! please input a number:")
8
9 product_cart = [['iphone6s',5800], #定义商品列表
10 ['macbook',9000],
11 ['coffee',30],
12 ['python book',80],
13 ['bicycle',1500]
14 ]
15 shopping_cart = [] #定义购物车
16 balance=salary
17
18 while True:
19 for i,v in enumerate(product_cart,1): #enumerate参数将商品列表循环打印，并且第一行从1开始 加上序号
20 print(i,v)
21
22 choise = input("please input your selection[typing 'q' to quit]:")
23 if choise.isdigit(): #判断是否是数字
24 choise=int(choise)
25 if choise >=1 and choise<=len(product_cart): #判断输入的字符是否符合商品列表所在的范围
26 sales =product_cart[choise-1] #将用户选择的商品赋值给sales
27 if balance >=sales[1]: #判断余额是否足够购买该商品
28 balance -=sales[1] #购买完后将余额减去商品价格
29 shopping_cart.append(sales) #将商品加入购物车
30 print("your balance is %s :"%balance)
31 print()
32 else:
33 print("your balance is %s,not enough to buy this one，please try another products!"%balance,)
34 print()
35
36
37 else:
38 print("no such a selection")
39 elif choise == 'q': #判断是否是q选择退出
40 print("your shopping cart is:")
41 for i, v in enumerate(shopping_cart, 1):
42 print(i, v)
43 break
44 else:
45 print("Invalid typing.please typing a number!") #非数字执行的操作
