using System;
using System.Collections.Generic;
using System.Text;

public class Program
{
    public void Proc(){
        Reader.IsDebug = false;
        int[] inpt = Reader.GetInt(' ', true);
        int stationCount = inpt[0];
        int nimptsuMax = inpt[1];
        List<int> itemList = new List<int>();
        
        for(int i=0; i<stationCount; i++) {
            int newNimotsu = int.Parse(Reader.ReadLine());
            int idx = 0;
            if(itemList.Count > 0) {
                idx = GetIndex(itemList, Math.Abs(newNimotsu), 0,  itemList.Count - 1);
            }
            if(newNimotsu > 0) {
                if(itemList.Count - idx >= nimptsuMax) {
                    // 荷物つまない
                } else
                {
                    itemList.Insert(idx, newNimotsu);
                }
            } else
            {
                if(idx < itemList.Count && itemList[idx] == Math.Abs(newNimotsu)) {
                    itemList.RemoveAt(idx);
                }
            }
            
        }
        int ans = itemList.Count;
        Console.WriteLine(ans);
    }
    
    private int GetIndex(List<int> target, int item, int minIdx, int maxIdx) {
        if(target[minIdx] >= item) {
            return minIdx;
        }
        if(target[maxIdx] < item) {
            return maxIdx + 1;
        }
        
        int mid = (minIdx + maxIdx) / 2;
        
        if(mid == minIdx) {
            return maxIdx;
        }
        if(target[mid] >= item) {
            return GetIndex(target, item, minIdx, mid);
        } else
        {
            return GetIndex(target, item, mid, maxIdx);
        }
        
    }
    
    
    
    
    public static void Main(string[] args)
    {
        Program prg = new Program();
        prg.Proc();
    }
}

class Reader
{
    public static bool IsDebug = true;
    
    private static System.IO.StringReader sr;
    
    public static string ReadLine() {
        if(IsDebug) {
            if(sr == null) {
                sr = new System.IO.StringReader(initStr.Trim());
            }
            return sr.ReadLine();
        } else {
            return Console.ReadLine();
        }
    }
    
    public static int[] GetInt(char delimiter = ' ', bool mustTrim = false) {
        string src = ReadLine();
        if(mustTrim) {
            src = src.Trim();
        }
        string[] inpt = src.Split(delimiter);
        int[] ret = new int[inpt.Length];
        for(int i=0; i<inpt.Length; i++) {
            string item = inpt[i];
            if(mustTrim) {
                item = item.Trim();
            }
            ret[i] = int.Parse(item);
        }
        return ret;
    }
    
    private static string initStr = @"






";
}