import Data.List
import Data.Maybe

table = ['A'..'Z']

solve :: Int -> String -> String
solve _ [] = []
solve n (s:ss) = res : solve n ss
  where res = table !! ((fromJust (s `elemIndex` table) + n) `mod` 26)

main :: IO ()
main = do
  n <- readLn
  s <- getLine
  putStrLn $ solve n s
