From 5539a4bd05bf8b6b95ab8680d515bd4c31d72eb2 Mon Sep 17 00:00:00 2001
From: George Thomas <georgefsthomas@gmail.com>
Date: Mon, 8 Dec 2025 15:52:20 +0000
Subject: [PATCH] Solve day 6 part 1

---
 haskell/Pre.hs          |  2 +-
 haskell/Puzzles/Day6.hs | 24 +++++++++++++++++++++---
 outputs/real/6/1        |  1 +
 3 files changed, 23 insertions(+), 4 deletions(-)
 create mode 100644 outputs/real/6/1

diff --git a/haskell/Pre.hs b/haskell/Pre.hs
index b2c44d4..4993d13 100644
--- a/haskell/Pre.hs
+++ b/haskell/Pre.hs
@@ -56,7 +56,7 @@ import Data.Char
 import Data.Foldable hiding (foldl1, foldr1, maximum, maximumBy, minimum, minimumBy)
 import Data.Foldable1
 import Data.Functor
-import Data.List (sortOn)
+import Data.List (sortOn, transpose)
 import Data.List.Extra (dropEnd, enumerate)
 import Data.List.NonEmpty (NonEmpty ((:|)), nonEmpty, some1)
 import Data.Maybe
diff --git a/haskell/Puzzles/Day6.hs b/haskell/Puzzles/Day6.hs
index 599d617..31ab853 100644
--- a/haskell/Puzzles/Day6.hs
+++ b/haskell/Puzzles/Day6.hs
@@ -2,14 +2,32 @@ module Puzzles.Day6 (puzzle) where
 
 import Pre
 
+import Data.Text.Lazy qualified as TL
+
 puzzle :: Puzzle
 puzzle =
     Puzzle
         { number = 6
-        , parser = pure ()
+        , parser = do
+            ints <- (hspace *> (decimal `sepBy1` hspace1)) `sepEndBy1` newline
+            ops <- ((single '*' $> Multiply) <|> (single '+' $> Add)) `sepEndBy` hspace1
+            void newline
+            pure (ops, transpose ints)
         , parts =
-            [ \() ->
-                "TODO"
+            [ TL.show
+                . sum
+                . uncurry (zipWith \op -> foldl' (apply op) (unit op))
             ]
         , extraTests = mempty
         }
+
+data Op = Add | Multiply
+    deriving (Eq, Ord, Show, Enum, Bounded)
+apply :: Op -> Int -> Int -> Int
+apply = \case
+    Add -> (+)
+    Multiply -> (*)
+unit :: Op -> Int
+unit = \case
+    Add -> 0
+    Multiply -> 1
diff --git a/outputs/real/6/1 b/outputs/real/6/1
new file mode 100644
index 0000000..d210b1e
--- /dev/null
+++ b/outputs/real/6/1
@@ -0,0 +1 @@
+8108520669952
\ No newline at end of file