CodinGame - APU: Init Phase

initphase.hs

import Control.Monad
import Data.List

main = do
    [ _, height ] <- replicateM 2 (fmap read getLine)
    cells <- fmap concat (forM [0 .. height - 1] (\ y -> fmap (parseRow y) getLine))
    forM cells (putStrLn . findNext cells)
    where
        parseRow y cells = map ((,) y . fst) $ filter ((==) '0' . snd) $ zip [0..] cells

findNext cells cell@(y, x) =
    unwords (map showCell [cell, fallback right, fallback below])
    where
        right = filter (\ (y', x') -> y == y' && x' > x) cells
        below = filter (\ (y', x') -> x == x' && y' > y) cells
        fallback [] = (-1, -1)
        fallback (cell : _) = cell

showCell (y, x) = show x ++ " " ++ show y