Started on part 2

app/9.hs

@@ -3,7 +3,9 @@ module Main where
 
 import Data.Functor
 import Data.List
-import Data.List.Extra
+import Data.List.Split
+import Data.List.Extra hiding (split)
+import Debug.Trace
 
 data ℜ where
   None :: ℜ
@@ -24,11 +26,25 @@ sort1 s
                   None -> sort1 $ init s
                   n    -> sort1 $ takeWhile (/= None) s ++ [n] ++ drop 1 (dropWhile (/= None) (init s))
 
+chunks :: [ℜ] -> [[ℜ]]
+chunks =
+  init . foldr (\a (x:xs) -> if a `elem` x then (a:x):xs else [a]:x:xs) [[]]
+
+fit :: [[ℜ]] -> [ℜ] -> [ℜ]
+fit s t = let (p,a) = break (elem None) s
+              (n,a') = span (elem None) a in
+            if null n then concat s ++ t else
+  concat p ++ if length n >= length t then t ++ concat a' ++ replicate (length n) None else fit a' t
+
 sort2 :: [ℜ] -> [ℜ]
-sort2 = undefined
+sort2 s = let c = chunks s -- TODO: needs more work here
+              fitted = fit (init c) (last c) in
+            if s == fitted then s else sort2 s
 
 solve :: ([ℜ] -> [ℜ]) -> [ℜ] -> Int
-solve f s = let fixed = (\(Num n) -> n) <$> f s in
+solve f s = let fixed = (\case
+                            Num n -> n
+                            None  -> 0) <$> f s in
   sum $ zipWith (*) fixed [0..]
 
 main :: IO ()