--- Writeup at https://work.njae.me.uk/2021/12/12/advent-of-code-2021-day-11/
+-- Writeup at https://work.njae.me.uk/2022/04/24/advent-of-code-2021-day-25/
-import qualified Data.Map as M
+import qualified Data.Map.Strict as M
import Data.Map.Strict ((!), (\\), (!?))
import Linear (V2(..), (^+^))
import Data.List (unfoldr)