fun main(args: Array<String>) {
    val n = readLine()!!.toInt()
    val s = readLine()!!

    val key = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
    val split = key.toCharArray()
    val map = split.mapIndexed { i, c ->
        c to split[if ((i + n) >= key.length) {
            i + n - key.length
        } else {
            i + n
        }]
    }.toMap()

    val joinToString = s.toCharArray().map { map[it] }.joinToString(separator = "")
    println(joinToString)

}
