import Data.List
import Data.Maybe
main = do
  n <- readLn :: IO Int
  xs <- getLine
  let cs = ['A'..'Z']
  putStrLn $ f xs n cs
  
f :: String -> Int -> String -> String
f "" _ _ = "" 
f (x:xs) n cs =
  let c = cs !! (((fromJust $ elemIndex x cs)+n) `mod` 26)
    in c : (f xs n cs)