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import Control.Monad
import qualified Data.Map.Strict as Map
import Data.Map.Strict ((!))
import Data.Maybe
data Ins = Ins String Int Cond
data Cond = Cond String (Int -> Bool)
type State = Map.Map String Int
initState :: State
initState = Map.empty
condTable :: Map.Map String (Int -> Int -> Bool)
condTable = Map.fromList
[("<", flip (<))
,(">", flip (>))
,("<=", flip (<=))
,(">=", flip (>=))
,("==", flip (==))
,("!=", flip (/=))]
parse :: String -> Ins
parse str = case words str of
[name, "inc", val, "if", cname, op, cval] ->
Ins name ( read val) (Cond cname ((condTable ! op) (read cval)))
[name, "dec", val, "if", cname, op, cval] ->
Ins name (-read val) (Cond cname ((condTable ! op) (read cval)))
exec :: State -> Ins -> State
exec mp (Ins name delta (Cond cname cop)) =
let val = fromMaybe 0 (Map.lookup name mp)
cval = fromMaybe 0 (Map.lookup cname mp)
in if cop cval then Map.insert name (val + delta) mp else mp
main :: IO ()
main = do
input <- liftM (map parse . lines) (readFile "8.in")
let states = scanl exec initState input
print $ maximum $ Map.elems (last states)
print $ maximum $ map (maximum . (0 :) . Map.elems) states
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