encoder :: [String] -> IO ()
encoder [key] = do

  plain  <- getContents

  let cypher = xor_decode key plain

  putStrLn cypher
encoder :: [String] -> IO ()
encoder [key] = do

  plain  <- getContents

  let cypher = xor_decode key plain

  putStrLn cypher
encoder [key] = do

  plain  <- getContents

  let cypher = xor_decode key plain

  putStrLn cypher