From b4855cb88ec82b139900a89f0efc53696b2fbdee Mon Sep 17 00:00:00 2001
From: Gattix <gattix@cock.li>
Date: Wed, 14 Dec 2022 01:47:09 +0100
Subject: [PATCH] day13 part 2

You can do it the easy way or the hard way. This is the hard way.
---
 2022/day13/day13.hs | 24 ++++++++++++++++--------
 1 file changed, 16 insertions(+), 8 deletions(-)

diff --git a/2022/day13/day13.hs b/2022/day13/day13.hs
index 25365ee..991c496 100644
--- a/2022/day13/day13.hs
+++ b/2022/day13/day13.hs
@@ -1,5 +1,3 @@
-{-# LANGUAGE OverloadedStrings #-}
-
 import Data.List
 import Data.List.Split
 import Data.Maybe
@@ -7,10 +5,10 @@ import qualified Data.Text as T
 
 main :: IO ()
 main = do
-  input <- map lines . splitOn "\n\n" <$> readFile "input"
-  let toDigit = T.unpack . T.replace "10" ":" . T.pack
+  let toDigit = T.unpack . T.replace (T.pack "10") (T.pack ":") . T.pack
+  input <- map (map toDigit . lines) . splitOn "\n\n" <$> readFile "input"
   print $
-    sum $ zipWith (*) [1 ..] $ map (fromEnum . isOrdered 0 . map toDigit) input
+    sum $ zipWith (*) [1 ..] $ map (fromEnum . isOrdered 0) input
   let divider = ["[[6]]", "[[2]]"]
   let sorted = sortBy mySort (divider ++ concat input)
   print $ product $ map (+ 1) $ mapMaybe (`elemIndex` sorted) divider
@@ -24,8 +22,6 @@ isOrdered n [l:ls, r:rs]
   | r == ']' = l == ',' && isOrdered (pred n) [l : ls, rs]
   | l == '[' = r /= ']' && isOrdered (pred n) [ls, r : rs]
   | r == '[' = l == ']' || isOrdered (succ n) [l : ls, rs]
-  | l == ',' = False
-  | r == ',' = True
   | l > r = False
   | l < r = True
   | otherwise = False
@@ -33,8 +29,20 @@ isOrdered _ [[], _] = True
 isOrdered _ [_, []] = False
 isOrdered _ _ = True
 
+addBrackets :: [String] -> [String] -> [String]
+addBrackets [accl,accr] [l:ls,r:rs]
+  | l == r = addBrackets [l:accl,r:accr] [ls,rs]
+  | l `elem` ['0'..':'] && r `elem` ['0' .. ':'] = addBrackets [l:accl,r:accr] [ls,rs]
+  | l == '[' = addBrackets [l:accl,l:accr] [ls,r:rs]
+  | r == '[' = addBrackets [r:accl,r:accr] [l:ls,rs]
+  | l == ']' = addBrackets [accl,r:accr] [l:ls,rs]
+  | r == ']' = addBrackets [l:accl,accr] [ls,r:rs]
+addBrackets [accl,accr]  ["",rs]= map reverse [accl,reverse rs ++ accr]
+addBrackets [accl,accr] [ls,""] = map reverse [reverse ls ++ accl,accr]
+addBrackets _ acc = map reverse acc
+
 mySort :: String -> String -> Ordering
 mySort x y =
-  if isOrdered 0 [x, y]
+  if isOrdered 0 (addBrackets ["",""] [x, y])
     then LT
     else GT