day 10

Signed-off-by: Amneesh Singh <natto@weirdnatto.in>

Lib.hs

@@ -1,6 +1,7 @@
-module Lib (readFile', split, count, tRead) where
+module Lib (readFile', tRead, buildGrid, split, count) where
 
 import Data.ByteString qualified as B (readFile)
+import Data.Map qualified as M
 import Data.Text (Text)
 import Data.Text.Encoding qualified as T (decodeUtf8)
 import Data.Text.Read qualified as TR
@@ -13,6 +14,10 @@ readFile' f = T.decodeUtf8 <$> B.readFile f
 tRead :: Text -> Int
 tRead = (\(Right (n, _)) -> n) . TR.signed TR.decimal
 
+-- Data.Map --
+buildGrid :: [[a]] -> M.Map (Int, Int) a
+buildGrid xs = M.fromList [((x, y), a) | (row, x) <- zip xs [0 ..], (a, y) <- zip row [0 ..]]
+
 -- Utility --
 split :: (Eq a) => a -> [a] -> [[a]]
 split delimiter list =