From fd4501f3c4948121a86a42883fe4cc2269116003 Mon Sep 17 00:00:00 2001
From: eriedaberrie <eriedaberrie@gmail.com>
Date: Mon, 2 Dec 2024 15:12:48 -0800
Subject: [PATCH] 2024 day 1: Haskell solutions

---
 2024/1/Main1.hs | 11 +++++++++++
 2024/1/Main2.hs | 14 ++++++++++++++
 flake.nix       |  1 +
 3 files changed, 26 insertions(+)
 create mode 100644 2024/1/Main1.hs
 create mode 100644 2024/1/Main2.hs

diff --git a/2024/1/Main1.hs b/2024/1/Main1.hs
new file mode 100644
index 0000000..8932eb8
--- /dev/null
+++ b/2024/1/Main1.hs
@@ -0,0 +1,11 @@
+import           Data.List (sort, transpose)
+import           Data.List.Split (splitOn)
+
+solve :: [[Int]] -> Int
+solve = sum . map abs . (\[x, xx] -> zipWith (-) x xx) . map sort
+
+main :: IO ()
+main =
+  print . solve . transpose . map parseLine . lines =<< readFile "data.txt"
+  where
+    parseLine = map read . filter (not . null) . splitOn " "
diff --git a/2024/1/Main2.hs b/2024/1/Main2.hs
new file mode 100644
index 0000000..192bb73
--- /dev/null
+++ b/2024/1/Main2.hs
@@ -0,0 +1,14 @@
+import qualified Data.IntMultiSet as IMultiSet
+import           Data.List (sort, transpose)
+import           Data.List.Split (splitOn)
+
+solve :: [[Int]] -> Int
+solve [l, r] = sum $ map (\x -> x * IMultiSet.occur x rs) l
+  where
+    rs = IMultiSet.fromList r
+
+main :: IO ()
+main =
+  print . solve . transpose . map parseLine . lines =<< readFile "data.txt"
+  where
+    parseLine = map read . filter (not . null) . splitOn " "
diff --git a/flake.nix b/flake.nix
index 9723b50..4c2e22a 100644
--- a/flake.nix
+++ b/flake.nix
@@ -33,6 +33,7 @@
               with p; [
                 containers
                 extra
+                multiset
                 regex-compat
                 split
                 text