mass rename

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

day08.hs

@@ -0,0 +1,48 @@
+import Data.List (scanl, tails, transpose, zip4, zipWith4)
+import Data.Text (Text)
+import qualified Data.Text as T (lines, unpack)
+import Lib (readFile')
+
+-- new approach was hinted by an anon but I cannot quite get it right
+-- a fun approach, not necessarily the fastest (or cleanest (or smartest))
+
+main :: IO ()
+main = do
+  input <- map T.unpack . T.lines <$> readFile' "day8.in"
+  putStr "Q1: "
+  print $ q1 input
+  putStr "Q2: "
+  print $ q2 input
+
+layer :: [[Char]] -> (a -> a -> a) -> ([[Char]] -> [[a]]) -> [[a]]
+layer input f f' =
+  zipWith4 ( zipWith4 (\w x y z -> f w . f x $ f y z) )
+    (f' e)
+    (map reverse $ f' w)
+    (transpose $ f' n)
+    (reverse . transpose $ f' s)
+  where
+    (e, w, n, s) =
+      ( input,
+        map reverse input,
+        transpose input,
+        transpose $ reverse input
+      ) -- (east, west, north, south]
+
+q1 :: [[Char]] -> Int
+q1 input = length . filter not . concat $ layer input (&&) q1'
+  where
+    q1' :: [[Char]] -> [[Bool]]
+    q1' = map (\x -> zipWith (<=) x $ scanl max minBound x)
+
+q2 :: [[Char]] -> Int
+q2 input = maximum . concat $ layer input (*) q2'
+  where
+    q2' :: [[Char]] -> [[Int]]
+    q2' =
+      map
+        ( \a ->
+            [ let l = length (takeWhile (< x) xs) in (+ l) . fromEnum $ length xs /= l
+              | (x : xs) <- tails a
+            ]
+        )