ByteSum.hs

module Main where

import System.Environment (getArgs)
import qualified Data.ByteString.Lazy as L
import Data.Word

addBytes :: [Word8] -> Word8
addBytes [] = 0
addBytes (x:xs) = x + addBytes xs

addBytes' :: [Word8] -> Word8
addBytes' = foldr (+) 0

addBytes'' :: [Word8] -> Word8
addBytes'' = sum

main :: IO ()
main = do
        args <- getArgs
        let filename = head args
        fc <- L.readFile filename
        print $ addBytes'' $ L.unpack fc