database = {"": ""}
while True:
    choice = int(input("網站登入介面\n1：登入\n2：註冊\n3：退出\n請選擇："))
    if choice == 1:
        print("歡迎來到登入介面")
        name = input("請輸入使用者名稱：")
        password = input("請輸入密碼：")
        a = {name: password}
        for i, j in database.items():
            if a == {i: j}:
                print("登入成功")
 

                break
        if a != {i: j}:
            print("登入失敗，請重新輸入")
        if a == {i: j}:
            break
    if choice == 2:
        print("歡迎來到註冊介面")
        name = input("請輸入使用者名稱：")
        password = input("請輸入密碼：")
        database.setdefault(name, password)
        print("註冊成功")
    if choice == 3:
 

        print("退出成功")
        break