home_page = """
❀❀================❀❀
    账号:******
    密码:******
    注册    登录  
❀❀================❀❀

请选择：
    1.注册  2.登录  3.退出
"""

def reg_num(str1):
    list1 = []
    with open('bb.txt', 'r', encoding='utf-8') as f:
        x = f.readline()
        while x:
            list1.append(x)
            x = f.readline()
        # list1 = list[x]
    if len(list1)==0:
        str2 = input('密码：')
        with open('bb.txt','a',encoding='utf-8') as f:
            f.write(str1+'\n')
            f.write(str2+'\n')
    else:
        for index in range(0,len(list1),2):
            if list1[index] == str1+'\n':
                print('此账号已被注册')
            else:
                str2 = input('密码：')
                with open('bb.txt', 'a', encoding='utf-8') as f:
                    f.write(str1+'\n')
                    f.write(str2+'\n')
    print('注册成功')
def ter_num(str1):
    list1 = []
    with open('bb.txt', 'r', encoding='utf-8') as f:
        x = f.readline()
        while x:
            list1.append(x)
            # print(list1)
            x = f.readline()
    # with open('bb.txt', 'r', encoding='utf-8') as f:
    #     list1 = list[f.read()]
    if str1+'\n' not in list1:
        print('无此账号,请重新输入')
    else:
        while 1:
            str2 = input('密码：')
            for index in range(0,len(list1),2):
                if list1[index] == str1+'\n':
                    while 1:
                        if list1[index+1] == str2+'\n':
                            print('登录成功')
                            break
                        else:
                            print('密码错误')
                            break
                    break
            break

with open('bb.txt', 'r', encoding='utf-8') as f:
    x = f.readline()
    print(x)
while 1:
    print(home_page)
    num1 = int(input('请输入：'))
    if num1 == 1:
        str1 = input('账号：')
        reg_num(str1)
        input('任意键返回')
    elif num1 == 2:
        str1 = input('账号：')
        ter_num(str1)
        input('系统维护中，任意键返回')

else:
    break