shorter

glguy · Dec 11, 2023 · 5278cb1 · 5278cb1
1 parent fa01dd9
commit 5278cb1
Showing 1 changed file with 5 additions and 9 deletions.
diff --git a/solutions/src/2023/11.hs b/solutions/src/2023/11.hs
@@ -1,4 +1,5 @@
 {-# Language QuasiQuotes, NumericUnderscores, ImportQualifiedPost #-}
+{-# OPTIONS_GHC -Wall -Wno-x-partial #-}
 {-|
 Module      : Main
 Description : Day 11 solution
@@ -11,9 +12,7 @@ Maintainer  : emertens@gmail.com
 -}
 module Main where
 
-import Data.Set (Set)
-import Data.Set qualified as Set
-import Data.List
+import Data.List (inits, tails)
 import Data.Map qualified as Map
 import Advent
 import Advent.Coord (coordLines, Coord(C))
@@ -30,13 +29,10 @@ main =
     let rows = Map.assocs (counts [y | C y _ <- galaxies])
     let cols = Map.assocs (counts [x | C _ x <- galaxies])
 
-    let solve1 n xs =
-          sum
-          [ (fst (head r) - fst (last l) - 1) * n * (sum (map snd l) * sum (map snd r))
+    let solve1 n xs
+          = sum
+          [ ((fst (head r) - fst (last l) - 1) * n + 1) * sum (map snd l) * sum (map snd r)
           | (l,r) <- zip (inits xs) (tails xs), not (null l), not (null r)]
-          + sum
-          [ sum (map snd l) * sum (map snd r)
-          | (l,r) <- zip (inits xs) (tails xs)]
 
     let solve n = solve1 n rows + solve1 n cols