import java.util.Scanner

object Main {
  def main(args: Array[String]): Unit = {
    val scanner = new Scanner(System.in)
    val N, S = scanner.nextLine()
    println(S.map(char => fun(char, N.toInt)))
  }
  
  def fun(char: Char, num: Int): Char = {
    val str = ('A' to 'Z').toList
    str(((str.indexOf(char) + num ) % str.length))
  }
}
