diff options
Diffstat (limited to 'Main.hs')
-rw-r--r-- | Main.hs | 66 |
1 files changed, 66 insertions, 0 deletions
@@ -0,0 +1,66 @@ +import Math +import System.Environment +import Data.List +import Text.Printf + +errorMessage :: String -> String + +errorMessage "" = "nd v1\nUsage: nd [-int, -prime, -factor, -hcf]" +errorMessage reason = "nd v1\nFAILURE: " ++ reason ++ "\nUsage: nd [-int, -prime, -factor, -hcf]" + +flagHandlerF :: [String] -> Int -> String -> ([String] -> String) -> String + +flagHandlerF args (-1) error fmessage = + if (length args) == 0 + then error + else + (fmessage args) + +flagHandlerF args nargs error fmessage = + if (length args) /= nargs + then error + else + (fmessage args) + +flagHandler :: String -> [String] -> String + +flagHandler "-prime" args = + flagHandlerF args (-1) + (errorMessage "-prime requires at least one integer argument") + (\args -> + foldl (++) "" [show y ++ ": isPrime=" ++ (show $ isPrime y) + ++ "\n" | x <- args, let y = (read x) :: Int]) + +flagHandler "-factor" args = + flagHandlerF args (-1) + (errorMessage "-factor requires at least one integer argument") + (\args -> + foldl (++) "" [show y ++ ": factors=" ++ show (factors $ y) + | x <- args, let y = (read x) :: Int]) + +flagHandler "-int" args = + flagHandlerF args (-1) + (errorMessage "-int requires at least one integer argument") + (\args -> + foldl (++) "" [show y ++ ": (isPrime=" ++ (show $ isPrime y) + ++ ", factors=" ++ (show $ factors y) + ++ ")\n" | x <- args, let y = (read x) :: Int]) + +flagHandler "-hcf" args = + flagHandlerF args (2) + (errorMessage "-hcf requires two integer arguments") + (\args -> + let n = (read $ head args) :: Int + m = (read $ head $ tail args) :: Int + hcf = head $ reverse $ intersect (factors n) (factors m) in + "hcf(" ++ show n ++ ", " ++ show m ++ "): hcf=" ++ show hcf) + + +flagHandler _ _ = errorMessage "Didn't recognise flag" + +main = do + args <- getArgs + if (length args) == 0 + then putStrLn $ errorMessage "" + else + putStrLn $ flagHandler (head args) (tail args) |