diff --git a/2021/day04/day04.hs b/2021/day04/day04.hs
index 18b6b9a..c370615 100644
--- a/2021/day04/day04.hs
+++ b/2021/day04/day04.hs
@@ -12,8 +12,7 @@ main = do
   (i:is) <- splitOn "\n\n" <$> readFile "input"
   let nums = read $ '[' : i ++ "]" :: [Int]
   let boards =
-        map (map (flip zip (repeat False) . map read . words) . lines) is :: [[[( Int
-                                                                                , Bool)]]]
+        map (map (flip zip (repeat False) . map read . words) . lines) is :: [Board]
   let (newBoards, newNums) = bingo (boards, nums)
   print $ countScore newNums $ getWinBoard newBoards
   let ([lb], ln) = loseBoard (newBoards, newNums)