Day 8

2019/day8/day8.hs

@@ -0,0 +1,14 @@
+import Data.List.Split
+import Data.List
+
+main = do
+    content <- chunksOf (25*6) <$> head <$> lines <$> readFile "input"
+    print (day8a content)
+    putStrLn (day8b content)
+
+toLayers xs = snd $ minimum [((length . filter (=='0')) x, x) | x <- xs]
+day8a xs = let l = toLayers xs in
+    (length $ filter (=='2') l) * (length $ filter (=='1') l)
+
+day8b xs = intercalate "\n" $ map (map (\x->if x=='0' then ' ' else '•')) $ chunksOf 25 img
+    where img = map (foldr (\x y->if x=='2' then y else x) '2') $ transpose xs