AOC Day 1

src/AOC/Year2024/Quest01.purs

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+module AOC.Year2024.Quest01 where
+
+import PCC.Lib
+
+import Data.Array (transpose, zipWith)
+import Data.Array as Array
+import Data.CommutativeRing ((*))
+import Data.Eq ((==))
+import Data.EuclideanRing ((-))
+import Data.Foldable (sum)
+import Data.Function (($), (<<<))
+import Data.Functor (map)
+import Data.Ord (abs)
+import Data.Semigroup ((<>))
+import Data.Show (show)
+import Data.String.Utils (lines, words)
+import Data.Tuple (Tuple(..))
+import Data.Unit (Unit)
+import Effect (Effect)
+import Effect.Class.Console (log)
+
+--------------------------------------------------------------------------------
+-- Write your solutions here
+
+part1 :: String -> Effect Unit
+part1 input = do
+  let datums = map Array.sort $ transpose $ map (Array.mapMaybe parseInt10 <<< words) $ lines input
+  let result = case datums of
+        [left, right] -> sum $ zipWith (\a b -> abs (a - b)) left right
+        _ -> 0
+  log $ "Part 1 ==> " <> show result
+
+part2 :: String -> Effect Unit
+part2 input = do
+  let datums = transpose $ map (Array.mapMaybe parseInt10 <<< words) $ lines input
+  let Tuple left right = case datums of
+        [left, right] -> Tuple left right
+        _ -> Tuple [] []
+  let result = sum $ map (\n -> n * countMatching (_ == n) right) left
+  log $ "Part 2 ==> " <> show result
+
+--------------------------------------------------------------------------------
+