using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Numerics;
using System.Text;
using static System.Console;
using static System.Convert;
using static System.Math;
using static Extentions;

class IO
{
    int idx;
    string[] input = In.ReadToEnd().Split(new[] { " ", "\n", "\r" },
        StringSplitOptions.RemoveEmptyEntries);

    T Get<T>(Func<string, T> parser) => parser(input[idx++]);

    public string S => Get(s => s);
    public char C => Get(char.Parse);
    public int I => Get(int.Parse);
    public long L => Get(long.Parse);
    public double F => Get(double.Parse);
    public decimal D => Get(decimal.Parse);
    public BigInteger B => Get(BigInteger.Parse);

    T[] Gets<T>(int n, Func<string, T> parser)
        => input.Skip((idx += n) - n).Take(n).Select(parser).ToArray();

    public string[] Ss(int n) => Gets(n, s => s);
    public char[] Cs(int n) => Gets(n, char.Parse);
    public int[] Is(int n) => Gets(n, int.Parse);
    public long[] Ls(int n) => Gets(n, long.Parse);
    public double[] Fs(int n) => Gets(n, double.Parse);
    public decimal[] Ds(int n) => Gets(n, decimal.Parse);
    public BigInteger[] Bs(int n) => Gets(n, BigInteger.Parse);

    public void Write<T>(params T[] xs) => WriteLine(string.Join(" ", xs));
    public void Write(params object[] xs) => WriteLine(string.Join(" ", xs));
}

interface IMonoid<T>
{
    T Mempty { get; }
    T Mappend(T a, T b);
}

class Monoid<T> : IMonoid<T>
{
    public T Mempty { get; private set; }
    public Func<T, T, T> mappend;
    public T Mappend(T a, T b) => mappend(a, b);

    public Monoid(T mempty, Func<T, T, T> mappend)
    {
        this.Mempty = mempty;
        this.mappend = mappend;
    }
}

class IntSumMonoid : IMonoid<int>
{
    public int Mempty => 0;
    public int Mappend(int a, int b) => a + b;
}

interface IGroup<T> : IMonoid<T>
{
    T InvMappend(T a, T b);
}

class IntSumGroup : IntSumMonoid, IGroup<int>
{
    public int InvMappend(int a, int b) => a - b;
}

class BinaryIndexedTree<T>
{
    T[] tree;

    public readonly int N;
    public readonly IMonoid<T> Monoid;
    readonly bool supportsGroup = false;
    
    // O(N)
    public BinaryIndexedTree(int n, IMonoid<T> monoid)
    {
        N = n;
        Monoid = monoid;
        tree = Enumerable.Repeat(monoid.Mempty, n + 1).ToArray();
    }

    // O(N)
    public BinaryIndexedTree(IEnumerable<T> collection, IMonoid<T> monoid)
    {
        N = collection.Count();
        Monoid = monoid;
        tree = new T[N + 1];
        for (var i = 0; i < N; i++) tree[i + 1] = collection.ElementAt(i);
        for (var i = 1; i < N; i++)
        {
            var j = i + (i & -i);
            if (j < N) tree[j] = monoid.Mappend(tree[j], tree[i]);
        }
    }

    // O(N)
    public BinaryIndexedTree(int n, IGroup<T> group)
        : this(n, (IMonoid<T>)group)
    {
        supportsGroup = true;
    }

    // O(N)
    public BinaryIndexedTree(IEnumerable<T> collection, IGroup<T> group)
        : this(collection, (IMonoid<T>)group)
    {
        supportsGroup = true;
    }

    public T this[int i]
    {
        // O(log N)
        get { return this[i, i]; }

        // O(log N)
        set
        {
            if (!supportsGroup) throw new InvalidOperationException();
            var group = (IGroup<T>)Monoid;
            Append(i, group.InvMappend(value, this[i]));
        }
    }

    public T this[int i, int j]
    {
        // O(log N)
        get
        {
            if (!supportsGroup) throw new InvalidOperationException();
            var group = (IGroup<T>)Monoid;
            var acc = group.Mempty;
            j++;
            for (; j > i; j -= j & -j) acc = group.Mappend(acc, tree[j]);
            for (; i > j; i -= i & -i) acc = group.InvMappend(acc, tree[i]);
            return acc;
        }
    }

    // O(log N)
    public T Concat(int i)
    {
        var acc = Monoid.Mempty;
        for (i++; i > 0; i -= i & -i) acc = Monoid.Mappend(acc, tree[i]);
        return acc;
    }

    // O(log N)
    public void Append(int i, T d)
    {
        for (i++; i <= N; i += i & -i) tree[i] = Monoid.Mappend(tree[i], d);
    }
}

static class Extentions
{
}

static class Program
{
    public static void Main()
    {
        var sw = new StreamWriter(OpenStandardOutput()) { NewLine = "\n" };
#if DEBUG
        sw.AutoFlush = true;
#else
        sw.AutoFlush = false;
#endif
        SetOut(sw);
        Solve(new IO());
        Out.Flush();
    }

    static void Solve(IO io)
    {
        const int wMax = 1000000;

        var n = io.I;
        var k = io.I;
        var bit = new BinaryIndexedTree<int>(wMax, new IntSumGroup());

        for (var i = 0; i < n; i++)
        {
            var w = io.I;
            if (w > 0 && bit[w, wMax - 1] < k) bit[w]++;
            if (w < 0 && bit[-w] > 0) bit[-w]--;
        }

        io.Write(bit.Concat(wMax - 1));
    }
}