fun main(args: Array<String>) {
    val N = readInputLine().toInt()
    val S = readInputLine().toCharArray()
    
    for ((i, c) in S.withIndex()) {
        S[i] = ((c.toInt() - 'A'.toInt() + N) % ('Z'.toInt() - 'A'.toInt() + 1) + 'A'.toInt()).toChar()
    }
    
    println(S.joinToString(""))
}

fun readInputLine(): String {
    return readLine()!!
}
