import sequtils,strutils,algorithm,math,sugar,macros
template times*(n:int,body:untyped): untyped = (for _ in 0..<n: body)
template `max=`*(x,y:typed):void = x = max(x,y)
template `min=`*(x,y:typed):void = x = min(x,y)

proc getchar_unlocked():char {. importc:"getchar_unlocked",header: "<stdio.h>" .}
proc scan(): int =
  result = 0
  var minus = false
  while true:
    var k = getchar_unlocked()
    if k == '-' : minus = true
    elif k < '0' or k > '9': break
    else: result = 10 * result + k.ord - '0'.ord
  if minus: result *= -1


var data : array[100_0001,int]
let n = scan()
var last = 0
let k = scan()
proc update(i:int,val:int) =
  var i = i
  while i < 100_0001:
    data[i] += val
    i = i or (i + 1)
proc get(i:int): int =
  var i = i
  while i >= 0:
    result += data[i]
    i = (i and (i + 1)) - 1

n.times:
  let w = scan()
  if w > 0:
    if last - get(w-1) >= k: continue # W以上の荷物がK個以上
    update w, 1
    last += 1
  else:
    if get(-w-1) == get(-w) : continue # 荷物が無い
    update -w,-1
    last -= 1
echo last