fun main(args: Array<String>) {
    val n = readLine()?.toInt() ?: return
    val s = readLine() ?: return
    val a = hashMapOf<Char, Int>().apply {
        repeat(26) {
            this['A' + it] = it
        }
    }
    val i = hashMapOf<Int, Char>().apply {
        repeat(26) {
            this[it] = 'A' + it
        }
    }
    s.mapNotNull {
        val c = a[it]!!
        val index = c + n
        if (index >= 26) {
            i[index - 26]
        } else {
            i[index]
        }
    }.joinToString("").let {
        println(it)
    }
}