import Control.Applicative
import Control.Monad
import Data.Array
import Data.Array.ST
import Data.List
import Data.Ord (comparing)

big = 2^31
solve n c arr = let r = fmap snd go in if r == [] then -1 else minimum r where
  go = filter (\(k,v) -> fst k == n && v /= big) $ assocs arr'
  arr' = solve' n c arr

solve' n c arr = last go where
  acc0 = (listArray ((1,0),(n,c)) $ repeat big) // [((1,c),0)]
  go = unfoldr f (1,acc0)

  f (i,acc)
    | i > n = Nothing
    | otherwise = Just (acc', (i+1,acc')) where
      current = filter (\(j,_) -> fst j == i) $ assocs acc
      acc' = accum min acc $ [((t,c-y),m+m0)|((i,c),m0) <- current, (t,y,m) <- arr!i, c-y >= 0]

main = do
  n <- (read :: String -> Int) <$> getLine
  c <- (read :: String -> Int) <$> getLine
  _ <- getLine
  ss <- fmap (read :: String -> Int) . words <$> getLine
  ts <- fmap (read :: String -> Int) . words <$> getLine
  ys <- fmap (read :: String -> Int) . words <$> getLine
  ms <- fmap (read :: String -> Int) . words <$> getLine
  
  let arr = accumArray (flip (:)) [] (1,n) $ zip ss $ zip3 ts ys ms
  print $ solve n c arr