import Data.Char

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

solve :: Int -> String -> String
solve n = map $ _chr . (`mod` 26) . (+ n) . _ord
  where
    _ord c = ord c - ord 'A'
    _chr i = chr $ i + ord 'A'