https://www.hackerrank.com/challenges/plus-minus/problem

gistfile1.txt

{-# LANGUAGE FlexibleInstances, UndecidableInstances, DuplicateRecordFields #-}

module Main where

import Control.Monad
import Data.Array
import Data.Bits
import Data.List
import Data.List.Split
--import Data.Set
import Debug.Trace
import System.Environment
import System.IO
import System.IO.Unsafe



-- divf :: a -> a -> b
p arr = fromIntegral $ length arr
divf a b = fromIntegral(a) / fromIntegral(b)
lengths a b = p a / p b 

f predicate arr = filter (predicate) arr

-- Complete the plusMinus function below.
plusMinus arr = do    
    print $  plus
    print $ minus
    print $ zeroes
    where     
        minus = lengths (f (<0) arr) arr
        zeroes = lengths (f (==0) arr) arr
        plus = lengths (f (>0) arr) arr

readMultipleLinesAsStringArray :: Int -> IO [String]
readMultipleLinesAsStringArray 0 = return []
readMultipleLinesAsStringArray n = do
    line <- getLine
    rest <- readMultipleLinesAsStringArray(n - 1)
    return (line : rest)

main :: IO()
main = do
    n <- readLn :: IO Int

    arrTemp <- getLine

    let arr = Data.List.map (read :: String -> Int) . words $ arrTemp

    plusMinus arr