diff --git a/2021/day12.hs b/2021/day12.hs
index dd0984a..b5c5399 100644
--- a/2021/day12.hs
+++ b/2021/day12.hs
@@ -1,42 +1,59 @@
 module Day12 where
-import Data.HashSet (HashSet, member, insert, fromList)
-import Data.Map ( Map, fromList, unionWith, empty, (!) )
+-- import Data.HashSet (HashSet, member, insert, fromList)
+-- import Data.Map ( Map, fromList, unionWith, empty, (!), insert, elems) qualified (map)
+import qualified Data.Map as M
+import qualified Data.Bits
+
+import Data.HashSet (HashSet)
+import qualified Data.HashSet as S
 import Data.List.Split (splitOn)
 import qualified Data.Char
 
-type Cave = String
+type Cave = Int
 type Path = (Cave,Cave)
-type System = Map Cave [Cave]
+type System = M.Map Cave [Cave]
 
 
-readPath :: String -> Path
+readPath :: String -> (String,String)
 readPath s = (from,to) where [from,to] = splitOn "-" s
 
-addPath :: Path -> System -> System
-addPath (from,to) = unionWith (++) (Data.Map.fromList [(from,[to]), (to,[from])])
+addPath :: (String,String) -> M.Map String [String] -> M.Map String [String]
+addPath (from,to) = M.unionWith (++) (M.fromList [(from,[to]), (to,[from])])
 
 isUpper :: Cave -> Bool
-isUpper = Data.Char.isUpper . head
+isUpper x = x < 0
 
 pathFinder :: System -> Cave -> HashSet Cave -> Int
-pathFinder sys "end" _ = 1
-pathFinder sys x visited = sum $ map (\next -> pathFinder sys next (next `insert` visited)) elig
-    where elig = filter (\cave -> isUpper cave || not (cave `member` visited)) (sys ! x)
+pathFinder sys (-1) _ = 1
+pathFinder sys x visited = sum $ map (\next -> pathFinder sys next (next `S.insert` visited)) elig
+    where elig = filter (\cave -> isUpper cave || not (cave `S.member` visited)) (sys M.! x)
 
 pathFinder2 :: System -> Cave -> HashSet Cave -> Int
-pathFinder2 sys "end" _ = 1
-pathFinder2 sys x visited = sum $ map (\next -> f next sys next (next `insert` visited)) elig
+pathFinder2 sys (-1) _ = 1
+pathFinder2 sys x visited = sum $ map (\next -> f next sys next (next `S.insert` visited)) elig
     where
-        f cave = if isUpper cave || not (cave `member` visited) then pathFinder2 else pathFinder
-        elig = filter (/= "start") (sys ! x)
+        f cave = if isUpper cave || not (cave `S.member` visited) then pathFinder2 else pathFinder
+        elig = filter (/= 1) (sys M.! x)
+
+convert :: [String] -> M.Map String Int
+convert caves = conversion
+    where
+        (conversion, numhi, numlo) = foldr go (M.fromList [("end", -1), ("start", 1)], 2, 1) caves
+        go cave (map,upper,lower)
+          | cave `M.member` map           = (map,upper,lower)
+          | Data.Char.isUpper (head cave) = (M.insert cave (-upper) map, upper+1, lower)
+          | otherwise                     = (M.insert cave (1 `Data.Bits.shiftL` lower) map, upper, lower+1)
 
 main :: IO ()
 main = do
     input <- map readPath . lines <$> getContents
-    let system = foldr addPath Data.Map.empty input
+    let system = foldr addPath M.empty input
+    let conversion = convert $ concat $ M.elems system
+    print conversion
+    let integralSystem = M.mapKeys (conversion M.!) $ M.map (map (conversion M.!)) system
 
     putStrLn "part 1: "
-    print $ pathFinder system "start" (Data.HashSet.fromList ["start"])
+    print $ pathFinder integralSystem 1 (S.fromList [1])
 
     putStrLn "part 2: "
-    print $ pathFinder2 system "start" (Data.HashSet.fromList ["start"])
+    print $ pathFinder2 integralSystem 1 (S.fromList [1])