import Data.Monoid
import System

r = foldr1 (+)

l = foldl1 (+)

m = getSum . mconcat . map Sum

main = do
  a <- getArgs
  print ((case a !! 0 of
            "r" -> r
            "l" -> l
            "m" -> m)
         [0 .. (read $ a !! 1)] :: Int)