=username_list = []

flag = 0

prize_dict = {'0': 'durex', '1': 'okamoto', '2': 'Jissbon'}
shopping_car_dict = {}

def register():
print('欢迎来到注册功能:')

username_register, userpwd_register = user_inp_func()
with open('user_info.txt', 'a', encoding='utf8') as fa:
    fa.write(f'{username_register}:{userpwd_register}\n')

    print(f'用户{username_register}注册成功')

def login():
if username_list:
print('请勿重复登陆.')
# if not judgement():
# print('请勿重复登陆.')

login_count = 0
while login_count < 3:
    username_inp, userpwd_inp = user_inp_func()
    with open('user_info.txt', 'r', encoding='utf8') as fr:
        for user_info in fr:
            user_info = user_info.strip()
            username_login, userpwd_login = user_info.split(':')

            if username_login == username_inp and userpwd_login == userpwd_inp:
                print('登录成功')
                # global flag
                # flag = 1
                login_count = 3
                username_list.append(username_login)
                break

        else:
            print('账号密码错误')
            login_count += 1

def logout():
# if not flag :
# print('请先登录.')
# return
if not username_list:
print('请先登录.')
return

username_list.clear()
print('注销成功.')

def shopping():
if not username_list:
print('请先登录.')
return

print('欢迎选购:')
print(prize_dict)
prize_choice = input('请输入商品代码:')
prize_name = prize_dict[prize_choice]
if not prize_choice in prize_dict:
    print('无效商品代码.')

if prize_name in shopping_car_dict:
    shopping_car_dict[prize_name] += 1
else:
    shopping_car_dict[prize_name] = 1

print(f'购买{prize_name}成功,购物车情况为:{shopping_car_dict}')

def shopping_car():
if not username_list:
print('请先登录.')
return

print(f'恭喜购物成功:{shopping_car_dict}')

shopping_car_dict.clear()

def user_inp_func():
username_inp = input('请输入用户名:')
userpwd_inp = input('请输入密码:')

return username_inp, userpwd_inp

def judgement():

if username_list:

print('请先登录后使用..')

return

else:

return 1

func_dict = {
'1': register,
'2': login,
'3': logout,
'4': shopping,
'5': shopping_car,
}

def start():
while 1:
print('''
1 注册
2 登录
3 注销
4 购物
5 购物车
q 退出
''')

    user_choice = input('请输入功能:(输入q退出)')
    if user_choice == 'q':
        break

    if user_choice not in func_dict:
        print('请输入正确功能键:')
        continue

    func_dict[user_choice]()

start()

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