let n=Int(readLine()!)!
let s=readLine()!

var ans = [Character]()

for c in s.unicodeScalars {
  if c.value >= 65 && c.value <= 90 {
    var x = Int(c.value) + n
    if x >= 91 {
      x = x - 91 + 65
    }
    let a = Character(UnicodeScalar(x))
    ans += [a]
  }
}

print(String(ans))