代码练习，购物车

1. 高亮显示提示

2. 启动程序后，先登录，登录成功则让用户输入充值钱数,然后打印商品列表，失败则重新登录，超过三次则退出程序

3. 允许用户根据商品编号购买商品

4. 用户选择商品后，检测余额是否够，够就直接扣款，不够就提醒

5. 可随时退出，退出时，打印已购买商品

#   -*- coding:utf-8 -*- dic = {'alex': {'password': 'qwer', 'count': 0, 'balance': 0},        'lilei': {'password': 'asdf', 'count': 0, 'balance': 0},        'jim': {'password': 'zxcv', 'count': 0, 'balance': 0}} goods = [     {"name": "电脑", "price": 1999},     {"name": "鼠标", "price": 10},     {"name": "游艇", "price": 20},     {"name": "美女", "price": 998}, ] shopping_cart = [] light_s = '\033[1;31;46m%s元\033[0m' loop = True while loop:     f = open(file='blacklist.txt', mode='r', encoding='utf-8')     blacklist = f.read()     f.closed     input_user = input('请输入您的用户名：').strip()     if input_user in blacklist:         print('很抱歉您的账户已被锁定')     else:         if input_user in dic:             input_password = input('请输入您的密码：').strip()             if input_password == dic[input_user]['password']:                 print('登录成功，您的账户余额还有', light_s % (dic[input_user]['balance']))                 recharge = input('是否进行充值？请输入充值的钱数，回车键继续')                 if recharge.isdigit():                     recharge = int(recharge)                     dic[input_user]['balance'] += int(recharge)                     print('当前余额为:', light_s % (dic[input_user]['balance']))                 print('商品列表'.center(50, '-'))                 print('-序号-', '商品'.center(4, '-'), '价格'.center(4, '-'))                 while loop:                     for index, i in enumerate(goods):                         print(' %s    %s   %s ' % (index, i['name'], i['price']))                     choice = input("请输入您要购买的商品序号,按'q'键退出")                     if choice.isdigit():                         choice = int(choice)                         if choice >= len(goods):                             print('\033[1;31;46m您所选择的商品不存在\033[0m')                             continue                         if dic[input_user]['balance'] >= int(goods[choice]['price']):                             dic[input_user]['balance'] -= int(goods[choice]['price'])                             print('购买成功，花费', light_s % (goods[choice]['price']), '余额还剩',                                   light_s % dic[input_user]['balance'])                             shopping_cart.append(goods[choice])                         else:                             print('余额不足，您的账户余额还有', light_s % (dic[input_user]['balance']))                             recharge = input('是否进行充值？请输入充值的钱数，回车键继续')                             if recharge.isdigit():                                 recharge = int(recharge)                                 dic[input_user]['balance'] += int(recharge)                                 print('当前余额为:', light_s % (dic[input_user]['balance']))                     elif choice == 'q':                         print('您购买的商品列表清单如下')                         for i in shopping_cart:                             print(i['name'], i['price'])                         print('\033[1;31;46m欢迎再来\033[0m')                         loop = False                     else:                         print('\033[1;31;46m请输入正确的序号\033[0m')             else:                 print('\033[1;31;46m密码错误\033[0m')                 dic[input_user]['count'] += 1                 if dic[input_user]['count'] > 2:                     f = open(file='blacklist.txt', mode='a', encoding='utf-8')                     f.write('%s ' % input_user)                     print('\033[1;31;46ml您的账号已被加入黑名单\033[0m')                     f.closed                     break         else:             print('您输入的用户名不存在')