python-----購物車

# -*- coding: utf-8 -*-
# Author   :Gogh
# @Time    :2017/12/12 11:30
# @Email   :[email protected]
product_list = [
    ('Mac', 9000),
    ('kindle', 800),
    ('tesla', 900000),
    ('python book', 105),
    ('bike', 2000),

]
saving = input('please input your money:')
shopping_car = []
if saving.isdigit():
    saving = int(saving)
    while True:
        # 打印商品內容
        for i, v in enumerate(product_list, 1):
            print(i, '>>>>', v)

            # 引導用戶選擇商品
        choice = input('選擇購買商品編號[退出：q]：')
        # 驗證輸入是否合法
        if choice.isdigit():
            choice = int(choice)
            if choice > 0 and choice <= len(product_list):
                # 將用戶選擇商品通過choice取出來
                p_item = product_list[choice - 1]
                # 如果錢夠，用本金saving減去該商品價格，並將該商品加入購物車
                if p_item[1] < saving:
                    saving -= p_item[1]
                    shopping_car.append(p_item)
                else:
                    print('餘額不足，還剩%s' % saving)
                print('你已經購買商品''>>>>>>', p_item)
            else:
                print('編碼不存在')
        elif choice == 'q':
            print('------------您已經購買如下商品----------------')
            # 循環遍歷購物車裏的商品，購物車存放的是已買商品
            for i in shopping_car:
                print(i)
            print('您還剩%s元錢' % saving)
            break
        else:
            print('invalid input')