购物车程序

# -*- coding: utf-8 -*-
# @Time    : 2020/7/26 14:13
# @Author  : Breeze
# @FileName: 购物车程序.py


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:
        #打印商品内容
        for i,v in enumerate(product_list,1):
            print(i,">>>>",v)
            # print(product_list.index(i)+1,i)
            #引导用户选择商品
        choice = input("选择购买商品编号[退出：q]：")
        #验证是否合法
        if choice.isdigit():
            choice = int(choice)
            if choice >0 and choice <= len(product_list):
                #将用户选择商品通过choice取出来
                p_item = product_list[choice-1]
                #如果钱够，用本金saving-该商品价格，并将该商品加入购物车
                if p_item[1]<saving:
                    saving -= p_item[1]
                    shopping_car.append(p_item)
                else:
                    print("余额不足，还剩%s"%saving)
                print(p_item)

            else:
                print("编码不存在")
        elif choice == 'q':
            print("--------您已购买以下商品--------")
            #循环遍历购物车里的商品，购物车存放的是已买商品
            for i in shopping_car:
                print(i)
            print("您还剩%s元"%saving)
            break
        else:
            print("Invalid input")
else:
    print("must be digit!")