import random


def main_func():
    num = random.randint(0000, 9999)
    random.seed(num)
    account_identifier = random.randint(0, 9)
    check_sum = random.randint(0, 9)
    user_card = int(f"400000{random.randint(1000000, 9999999)}{account_identifier}{random.randint(0, 9)}{check_sum}")
    user_pin_card = int('{:04d}'.format(random.randrange(0000, 9999)))
    user_balance = 0

    user_data = []


    exit_from_main_cycle = False

    while not exit_from_main_cycle:
        inp_user = input("1. Create an account\n2. Log into account\n0. Exit\n>")
        print(" ")

        if inp_user == "1":
            if not user_data:
                print(f"Your card has been created\nYour card number:\n{user_card}\nEnter your PIN:\n{user_pin_card}")
                user_data.append([int(user_card), user_pin_card])
                print(" ")

        elif inp_user == "2":

            if len(user_data) != 0:

                loop_exit_condition = False

                while not loop_exit_condition:
                    check_card_number = int(input("Enter your card number:\n>"))
                    pin_code_check = int(input("Enter your PIN:\n>"))

                    if check_card_number == user_data[0][0] and pin_code_check == user_data[0][1]:
                        print(" ")
                        print("You have successfully logged in!\n")

                        while not loop_exit_condition:

                            select_after_authorization = input("1. Balance\n2. Log out\n0. Exit\n>")
                            print(" ")

                            if select_after_authorization == "1":
                                print(f"Balance: {user_balance}\n")
                                continue
                            elif select_after_authorization == "2":
                                loop_exit_condition = True
                                print("You have successfully logged out!")
                                print(" ")
                            elif select_after_authorization == "0":
                                loop_exit_condition = True
                                exit_from_main_cycle = True

                    else:
                        print("Wrong card number or PIN!")
                        continue
            else:
                continue

        elif inp_user == "0":
            print("Bye!")
            break



if __name__=="__main__":
    print(main_func())