import java.io.{BufferedReader, InputStreamReader}

object Main {
  def main(args: Array[String]): Unit = {
    val in = new BufferedReader(new InputStreamReader(System.in))
    val n = in.readLine().toInt
    val s = in.readLine()

    System.out.println(
      s.toCharArray.map { c =>
        String.valueOf(((c - 'A' + n) % 26 + 'A').asInstanceOf[Char])
      }.mkString("")
    )
  }
}
