{-# LANGUAGE BangPatterns #-}

import Data.List
import qualified Data.ByteString.Char8 as B
import Data.Maybe
import Data.Monoid

instance Monoid Int where
 mempty = 0
 mappend v w = v + w

data SegTree m = Leaf !m | Node !m !(SegTree m) !(SegTree m) deriving (Eq, Show)

type Index = Int
type Size = Int

val :: Monoid m => SegTree m -> m
val (Leaf v) = v
val (Node v _ _) = v

fromList :: Monoid m => Size -> [m] -> SegTree m
fromList 1 [x] = Leaf x
fromList n xs = Node (val left <> val right) left right
 where
  m = div n 2
  (xs1, xs2) = splitAt m xs
  left = fromList m xs1
  right = fromList (n - m) xs2

update :: Monoid m => Size -> SegTree m -> Index -> m -> SegTree m
update 1 (Leaf v) 1 x = Leaf (v <> x)
update _ (Leaf _) _ _ = undefined
update n (Node _ l r) i x
 | i <= m = Node (val left <> val r) left r
 | otherwise = Node (val l <> val right) l right
 where
  m = div n 2
  left = update m l i x
  right = update (n - m) r (i - m) x

query :: Monoid m => Size -> SegTree m -> Index -> Index -> m
query 1 (Leaf v) 1 1 = v
query _ (Leaf _) _ _ = undefined
query n (Node v l r) i j
 | (i, j) == (1, n) = v
 | j <= m = query m l i j
 | i > m = query (n - m) r (i - m) (j - m)
 | otherwise = query m l i m <> query (n - m) r 1 (j - m)
 where m = div n 2

maxv = 1000000

main = do
 [_,k] <- map read . words <$> getLine :: IO [Int]
 ws <- map (fst . fromJust . B.readInt) . B.words <$> B.getContents
 let seg = fromList maxv (replicate maxv 0)
 print (freight k seg ws)

freight k seg = val . foldl' (dp k) seg

dp k seg w
 | w < 0 && query maxv seg (abs w) (abs w) /= 0 = update maxv seg (abs w) (-1)
 | w > 0 && query maxv seg w maxv < k = update maxv seg w 1
 | otherwise = seg