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module Main where
import qualified Data.Array as A
import Input
main :: IO ()
main = do
input <- getInput 3
let height = length input
width = length (head input)
let grid = A.array ((0, 0), (height - 1, width - 1))
[((y, x), fromEnum (c == '#'))
| (y, row) <- zip [0..] input
, (x, c) <- zip [0..] row]
countSlope hor ver =
let nsteps = height `div` ver
in sum [grid A.! (ver * i, hor * i `mod` width) | i <- [0..nsteps-1]]
print (countSlope 3 1)
print (product (map (uncurry countSlope) [(1,1), (3,1), (5,1), (7,1), (1,2)]))
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