Project Euler 89 (0.02 s)

pr89.hs

import Roman
import System.Environment
import Data.Char (toUpper)
import Control.Arrow ((&&&))

redundantChars :: String -> Int
redundantChars = (\(x,y) -> length x - length y) . (id &&& (toRoman . fromRoman))

main = do
    romans <- getContents
    print . sum . map redundantChars . lines $ romans