diff --git a/2022/day16.hs b/2022/day16.hs
new file mode 100644
index 0000000..fea99aa
--- /dev/null
+++ b/2022/day16.hs
@@ -0,0 +1,101 @@
+import qualified Data.Map as M
+import qualified Data.Set as S
+import Data.List.Split (splitOn)
+import Debug.Trace (traceShowId, traceShow, trace)
+import Data.Maybe (fromMaybe)
+
+import Bfs
+import Data.List (maximumBy, permutations, delete)
+import Data.Function (on)
+
+data Valve = V { flow' :: Int, neighs' :: [String] } deriving Show
+type ZMap = M.Map String Valve
+
+data NzValve = NV { flow :: Int, dists :: M.Map String Int} deriving Show
+type NzMap = M.Map String NzValve
+
+parseValve :: String -> (String, Valve)
+parseValve xs = (name, V flow tunnels) where
+    name = words xs !! 1
+    flow = read $ last $ splitOn "=" (head $ splitOn ";" xs)
+    valves = splitOn ", " $ last (splitOn "tunnels lead to valves " xs)
+    singleValve = splitOn "tunnel leads to valve " xs
+    tunnels = if length singleValve == 1 then valves else [last singleValve]
+
+search' :: ZMap -> String -> String -> Int
+search' scan from to = dists M.! to where
+    dists = bfs f [(from,0)] M.empty
+    f x = neighs' (scan M.! x)
+
+
+prepass :: ZMap -> NzMap
+prepass xs = M.fromList $ concatMap f $ M.toList xs where
+    f (name, v@(V flow _)) = [(name, NV flow (M.fromList $ dists name)) | name == "AA" || flow > 0]
+    dists name = map (\target -> (target, search' xs name target)) (filter (/= name) allValves)
+    allValves = map fst . filter (\(name, V flow _) -> name == "AA" || flow > 0) $ M.toList xs
+
+
+
+
+type Memo = M.Map (S.Set String, String, Int) Int
+-- search :: Map -> S.Set String -> String -> Int -> Memo -> (Int, Memo)
+-- search scan active location n memo 
+--     | n <= 0 = (0, M.empty)
+--     | otherwise = (releasedPressure + fst best, snd best) where
+--         valve = scan M.! location
+--         openValve = [(S.insert location active, location, n-1) | S.notMember location active && flow valve > 0]
+--         releasedPressure = sum $ map (flow . (scan M.!)) (S.toList active)
+--         nop = [(active, location, n-1) | S.size active == M.size scan]
+--         move = map (\(name, dist) -> (active, name, n-dist)) (dists $ scan M.! location)
+--         actions = openValve ++ move ++ nop
+--         trace x = if n>=15 then traceShow (fst x) x else x
+--         best = trace $ maximumBy (compare `on` fst) $ map (\(a,l,n) -> search scan a l n memo) actions
+--         -- best = maybe best' (\b -> (b,memo)) (M.lookup (active, location, n) memo)
+--         -- best' = foldr f (0, memo) actions where
+--         --     f (a,l, newN) (i,m) = let (result, memo') = search scan a l newN m; b = max i result in
+--         --         trace (b, M.insertWith max (a,l, newN) b $ M.unionWith max m memo')
+
+perms :: Int -> NzMap -> [[String]]
+perms limit m = perms' "AA" limit elems where
+    elems = filter (/= "AA") $ M.keys m
+    perms' :: String -> Int -> [String] -> [[String]]
+    perms' current remaining [] = [[]]
+    perms' current remaining as = do
+        a <- as
+        let distance = dists (m M.! current) M.! a
+        if distance < remaining then do
+            let l = delete a as
+            ls <- perms' a (remaining-distance) l
+            pure $ a:ls
+        else pure [a]
+
+execPerm :: NzMap -> [String] -> Int -> String -> Int -> Int
+execPerm nzmap [] flowrate location remaining = remaining * flowrate
+execPerm nzmap (target:qs) flowrate location remaining
+    | remaining < 0 = 0
+    | distance >= remaining = remaining * flowrate
+    | otherwise = (distance * flowrate) + execPerm nzmap qs flowrate' target (remaining - distance)
+    where
+        valve = nzmap M.! location
+        distance = 1 + dists valve M.! target
+        flowrate' = flowrate + flow (nzmap M.! target)
+
+
+traceMap :: (Show a, Show b) => (a -> a -> Bool) -> (a -> b) -> [a] -> [b]
+traceMap cond f [] = []
+traceMap cond f [x] = [f x]
+traceMap cond f (x:y:xs)
+    | cond x y = let result = f x in traceShow (result, x) (result: traceMap cond f (y:xs))
+    | otherwise = f x : traceMap cond f (y:xs)
+
+main :: IO ()
+main = do
+    x <- prepass . M.fromList . map parseValve . lines <$> getContents
+    mapM_ print x
+
+    let all = perms 30 x
+    let exec p = execPerm x p 0 "AA" 30
+    let result = traceMap (\a b -> take 2 a /= take 2 b) exec all
+    putStr "part 1: "
+    print $ maximum result
+    -- print $ fst $ search x S.empty "AA" 30 M.empty
diff --git a/2022/inputs/day16 b/2022/inputs/day16
new file mode 100644
index 0000000..949deb7
--- /dev/null
+++ b/2022/inputs/day16
@@ -0,0 +1,56 @@
+Valve JI has flow rate=21; tunnels lead to valves WI, XG
+Valve DM has flow rate=3; tunnels lead to valves JX, NG, AW, BY, PF
+Valve AZ has flow rate=0; tunnels lead to valves FJ, VC
+Valve YQ has flow rate=0; tunnels lead to valves TE, OP
+Valve WI has flow rate=0; tunnels lead to valves JI, VC
+Valve NE has flow rate=0; tunnels lead to valves ZK, AA
+Valve FM has flow rate=0; tunnels lead to valves LC, DU
+Valve QI has flow rate=0; tunnels lead to valves TE, JW
+Valve OY has flow rate=0; tunnels lead to valves XS, VF
+Valve XS has flow rate=18; tunnels lead to valves RR, OY, SV, NQ
+Valve NU has flow rate=0; tunnels lead to valves IZ, BD
+Valve JX has flow rate=0; tunnels lead to valves DM, ZK
+Valve WT has flow rate=23; tunnels lead to valves OV, QJ
+Valve KM has flow rate=0; tunnels lead to valves TE, OL
+Valve NG has flow rate=0; tunnels lead to valves II, DM
+Valve FJ has flow rate=0; tunnels lead to valves AZ, II
+Valve QR has flow rate=0; tunnels lead to valves ZK, KI
+Valve KI has flow rate=9; tunnels lead to valves ZZ, DI, TL, AJ, QR
+Valve ON has flow rate=0; tunnels lead to valves LC, QT
+Valve AW has flow rate=0; tunnels lead to valves DM, AA
+Valve HI has flow rate=0; tunnels lead to valves TE, VC
+Valve XG has flow rate=0; tunnels lead to valves II, JI
+Valve II has flow rate=19; tunnels lead to valves LF, NG, OL, FJ, XG
+Valve VC has flow rate=24; tunnels lead to valves WI, HI, AZ
+Valve VJ has flow rate=0; tunnels lead to valves UG, AA
+Valve IZ has flow rate=0; tunnels lead to valves VF, NU
+Valve EJ has flow rate=0; tunnels lead to valves ZK, LC
+Valve DU has flow rate=12; tunnels lead to valves TC, UG, FM
+Valve ZK has flow rate=10; tunnels lead to valves JX, EJ, JW, QR, NE
+Valve XF has flow rate=25; tunnels lead to valves OP, VT
+Valve LC has flow rate=4; tunnels lead to valves FM, EJ, ON, AJ, PF
+Valve SV has flow rate=0; tunnels lead to valves XS, IY
+Valve LF has flow rate=0; tunnels lead to valves II, OV
+Valve DI has flow rate=0; tunnels lead to valves KI, BY
+Valve OP has flow rate=0; tunnels lead to valves YQ, XF
+Valve NQ has flow rate=0; tunnels lead to valves TC, XS
+Valve QJ has flow rate=0; tunnels lead to valves VT, WT
+Valve IY has flow rate=22; tunnel leads to valve SV
+Valve AJ has flow rate=0; tunnels lead to valves LC, KI
+Valve TE has flow rate=11; tunnels lead to valves QI, HI, KM, YQ
+Valve ZZ has flow rate=0; tunnels lead to valves KI, AA
+Valve VT has flow rate=0; tunnels lead to valves XF, QJ
+Valve OL has flow rate=0; tunnels lead to valves KM, II
+Valve TC has flow rate=0; tunnels lead to valves NQ, DU
+Valve TL has flow rate=0; tunnels lead to valves VF, KI
+Valve QT has flow rate=0; tunnels lead to valves AA, ON
+Valve BY has flow rate=0; tunnels lead to valves DM, DI
+Valve OV has flow rate=0; tunnels lead to valves LF, WT
+Valve VN has flow rate=0; tunnels lead to valves RR, BD
+Valve VF has flow rate=13; tunnels lead to valves OY, IZ, TL
+Valve BD has flow rate=17; tunnels lead to valves NU, VN
+Valve UG has flow rate=0; tunnels lead to valves VJ, DU
+Valve PF has flow rate=0; tunnels lead to valves LC, DM
+Valve RR has flow rate=0; tunnels lead to valves XS, VN
+Valve AA has flow rate=0; tunnels lead to valves QT, ZZ, AW, VJ, NE
+Valve JW has flow rate=0; tunnels lead to valves ZK, QI
diff --git a/2022/inputs/day16.test b/2022/inputs/day16.test
new file mode 100644
index 0000000..9f30acc
--- /dev/null
+++ b/2022/inputs/day16.test
@@ -0,0 +1,10 @@
+Valve AA has flow rate=0; tunnels lead to valves DD, II, BB
+Valve BB has flow rate=13; tunnels lead to valves CC, AA
+Valve CC has flow rate=2; tunnels lead to valves DD, BB
+Valve DD has flow rate=20; tunnels lead to valves CC, AA, EE
+Valve EE has flow rate=3; tunnels lead to valves FF, DD
+Valve FF has flow rate=0; tunnels lead to valves EE, GG
+Valve GG has flow rate=0; tunnels lead to valves FF, HH
+Valve HH has flow rate=22; tunnel leads to valve GG
+Valve II has flow rate=0; tunnels lead to valves AA, JJ
+Valve JJ has flow rate=21; tunnel leads to valve II