2020-12-19 13:13:13 +01:00
|
|
|
{-# LANGUAGE TypeSynonymInstances, FlexibleInstances, DataKinds #-}
|
|
|
|
|
|
|
|
|
|
module Day17 where
|
|
|
|
|
|
|
|
|
|
import AoC
|
2020-12-24 15:05:59 +01:00
|
|
|
import Conway
|
2020-12-19 13:13:13 +01:00
|
|
|
|
|
|
|
|
import Data.List
|
|
|
|
|
import Data.Vector.Sized (Vector)
|
|
|
|
|
import qualified Data.Vector.Sized as V
|
|
|
|
|
import Data.Set (Set)
|
|
|
|
|
import qualified Data.Set as S
|
|
|
|
|
|
|
|
|
|
instance (Num a, Eq a) => Index (Vector n a) where
|
|
|
|
|
neighbours i = filter (/= i) . V.mapM (flip map [-1, 0, 1] . (+)) $ i
|
|
|
|
|
addIndex = V.zipWith (+)
|
|
|
|
|
|
|
|
|
|
run6 :: (Index i, Ord i) => Set i -> Int
|
|
|
|
|
run6 = S.size . (!! 6) . iterate (update (==3) (`notElem` [2, 3]))
|
|
|
|
|
|
|
|
|
|
main = runAoC (toIndices . lines) (run6 . S.fromList . map extendIndex) (run6 . S.fromList . map (extendIndex . extendIndex))
|
|
|
|
|
where toIndices input = [V.fromTuple (row, col) :: Vector 2 Int | (row, line) <- zip [0..] input, (col, '#') <- zip [0..] line]
|
|
|
|
|
extendIndex = V.cons 0
|
