import java.lang.Math

fun main(args: Array<String>)
{
    val MOD: Long = 1000000007L // (1e+9)+7

    val n = readLine()!!.toInt()
    val s = readLine()!!.toCharArray()

    for (i in 0 until s.size) {
        var tmp = s[i].toInt()
        tmp += n
        if (tmp > 'Z'.toInt()) tmp = tmp % 'Z'.toInt() + 'A'.toInt() - 1
        s[i] = tmp.toChar()
    }

    println(s.joinToString(separator=""))
}
