author = "superman"


product_list = [
    (‘Iphone‘,5800),
    (‘Mac Pro‘,9800),
    (‘Bike‘,800),
    (‘Watch‘,10600),
    (‘Coffee‘,31),
    (‘Alex Python‘,120),
]
shopping_list = []
salary = input("Input your salary:")
if salary.isdigit():            #判斷工資是不是數字
    salary = int(salary)         #如果是數字就用Int的數據類型
    while True:                #進入死循環
 

        for index,item in enumerate(product_list):    #打印商品列表
            #print(product_list.index(item),item)
            print(index,item)
        user_choice = input("選擇要買嘛？>>>:")
        if user_choice.isdigit():           #判斷工資是數字類型
            user_choice = int(user_choice)
            if user_choice < len(product_list) and user_choice >=0:        #判斷商品元素數量
 

                p_item = product_list[user_choice]           #通過下標索引把商品取出來
                if p_item[1] <= salary:                 #買的起
                    shopping_list.append(p_item)             #能買得起就把商品添加到列表裏
                    salary -= p_item[1]                    #扣錢
                    print("Added %s into shopping cart,your current balance is \033[31;1m%s\033[0m" %(p_item,salary) )
 

                else:
                    print("\033[41;1m你的余額只剩[%s]啦，還買個毛線\033[0m" % salary)
            else:
                print("product code [%s] is not exist!"% user_choice)      #輸入的商品序號不存在
        elif user_choice == ‘q‘:
            print("--------shopping list------")
            for p in shopping_list:
                print(p)
            print("Your current balance:",salary)
            exit()
        else:
            print("invalid option")

python面試題常考的超市購物車系統