day04:购物车的练习(20170216)

product_list = [
    ('IPhone',5900),
    ('Mac pro',9800),
    ('Bike',800),
    ('Watch',16000),
    ('Coffee',35),
    ('Tea',88)
]
shopping_list = []
sum1 = 0
print (product_list)
salary = input("输入你的金额：")
if salary.isdigit():
    salary = int(salary)
    while True:
        for index,item in enumerate(product_list):
            #print(product_list.index(item),item)
            print (index,item)
        user_choice = input("输入你要买的商品编号(结算请输入q)：")
        if user_choice.isdigit():
            user_choice = int(user_choice)
            if user_choice < len(product_list) and user_choice >= 0:
                p_item = product_list[user_choice]
                if p_item[1] <= salary:   #判断余额是否够
                    shopping_list.append(p_item)
                    salary -= p_item[1]
                    sum1 +=p_item[1]
                    print ("成功添加 %s 到购物车，你的当前余额是%s元：" % (shopping_list,salary))
                else:
                    print("你的余额只剩%s元啦，快去充值吧!"% salary)
            else:
                print("你输入的产品编号%s不存在！"% user_choice)
        elif user_choice == 'q':
            print ("----shopping list------")
            for p in shopping_list:
                print(p)

            print("购买成功！你的购买总额为：%s元,当前余额是：%s元" % (sum1,salary))
            exit()
        else:
            print ("你输入无效的商品编号,请重新输入！")
            continue
else:
    print ("请输入正确的金额！")