#!/usr/bin/python3
# -*- coding: utf-8 -*-

import sys


def translate(text: str, key: str) -> str:
    """
    Takes input of text as a string, and key as a string.
    Translates the message.
    Returns the translated message as a string.
    """
    new_message = []
    for i in range(256):
        index = i * 8
        newChar = chr(ord(text[i]) ^ int(key[index : index + 8], 2))
        new_message.append(newChar)
    return "".join(new_message)


def main() -> None:
    key_num = int(sys.argv[2])
    with open(sys.argv[1], "r") as code_book:
        key = code_book.readlines()[key_num]
    with open(sys.argv[3], "r", newline="") as input_text:
        text = input_text.read()
    with open(sys.argv[4], "w", newline="") as outputFile:
        outputFile.write(translate(text, key))


if __name__ == "__main__":
    main()