import qualified Data.ByteString.Char8 as C
import Data.Char
import Data.Array.IO

main :: IO ()
main = do
  ss <- C.getLine
  xs <- newArray (0, 2000) '\0' :: IO(IOUArray Int Char)
  solve 0 ss xs
  printss 0 (C.length ss) xs
  putStrLn ""
  
printss :: Int -> Int -> IOUArray Int Char -> IO ()
printss i n xs = if i >= n then return() else printss2 i n xs  

printss2 :: Int -> Int -> IOUArray Int Char -> IO ()
printss2 i n xs = do
  c <- readArray xs i
  putChar c
  printss (i + 1) n xs

solve :: Int -> C.ByteString -> IOUArray Int Char -> IO ()
solve n ss xs
  | C.length ss <= n = return ()
  | otherwise = solve2 n ss xs

solve2 :: Int -> C.ByteString -> IOUArray Int Char -> IO ()
solve2 n ss xs = do
  let n2 = n + 1
  let d = mod n2 26
  let c = C.index ss n
  let x = mod (ord c - ord 'A' + 26 - d) 26 + ord 'A'
  writeArray xs n (chr x)
  solve (n + 1) ss xs
  
nextInt :: C.ByteString -> (Int, C.ByteString)
nextInt ss
  | isDigit x = nextInt2 0 ss
  | otherwise = nextInt $ C.tail ss
  where x = C.head ss

nextInt2 :: Int -> C.ByteString -> (Int, C.ByteString)
nextInt2 n ss
  | C.null ss = (n, ss)
  | isDigit y = nextInt2 (n * 10 + (digitToInt y)) ys
  | otherwise = (n, ys)
  where y  = C.head ss
        ys = C.tail ss