-findRepeat rGrid cGrid = head $ dropWhile test $ iterate go (rGrid, Map.empty, 0)
- where test (g, c, _) = g `Map.notMember` c
- go (g, c, i) = (rollCycle g cGrid, Map.insert g i c, (i + 1))
+findRepeat rGrid cGrid = head $ dropWhile test $ iterate go (rGrid, M.empty, 0)
+ where test (g, c, _) = g `M.notMember` c
+ go (g, c, i) = (rollCycle g cGrid, M.insert g i c, (i + 1))