Python题目3：购物车

输入工资，获得购物列表，如果金额足够，将商品放入购物清单，完成采购，显示购物清单。

roduct_list = [
    ('Iphone',5800),
    ('Mac Pro',9800),
    ('Bike',800),
    ('Watch',10600),
    ('Coffee',31),
    ('Python',120),
]

shopping_list = []
salary = input("Input your salary:")
if salary.isdigit():
    salary = int(salary)
    while True:
        # for item in product_list:
            # print(product_list.index(item),item)
        for index,item in enumerate(product_list):
            print(index,item)

        user_choice = input("选择采购商品>>>:")

        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: # 买得起
                    shopping_list.append(p_item)
                    salary -= p_item[1]
                    print("Added %s into shopping cart,your current balance is %s" %(p_item,salary))
                else:
                    print("you have only %s" % salary)
            else:
                print("product code [%s] is not exist" % user_choice)
        elif user_choice == "q":
            print("---------shopping list----------")
            for p in shopping_list:
                print(p)
            print("Your current balance:",salary)
            exit()
        else:
            print("wrong")