Once Bob got to a sale of old TV sets. There were n TV sets at that sale. TV set with index i costs ai bellars. Some TV sets have a negative price — their owners are ready to pay Bob if he buys their useless apparatus. Bob can «buy» any TV sets he wants. Though he's very strong, Bob can carry at most m TV sets, and he has no desire to go to the sale for the second time. Please, help Bob find out the maximum sum of money that he can earn.

Input

The first line contains two space-separated integers n and m (1 ≤ m ≤ n ≤ 100) — amount of TV sets at the sale, and amount of TV sets that Bob can carry. The following line contains n space-separated integers ai ( - 1000 ≤ ai ≤ 1000) — prices of the TV sets. 

Output

Output the only number — the maximum sum of money that Bob can earn, given that he can carry at most m TV sets.

Examples

Input

5 3
-6 0 35 -2 4


Output

8


Input

4 2
7 0 0 -7


Output

7
import java.util.*;
import java.io.*;
import java.math.*;

public class Main {

    private static FastReader fr = new FastReader();
    private static Helper hp = new Helper();
    private static StringBuilder result = new StringBuilder();

    public static void main(String[] args) {
        Task solver = new Task();
        solver.solve();
    }

    static class Task {

        public void solve() {
            int n = fr.ni();
            int max = fr.ni();
            PriorityQueue<Integer> minHeap = new PriorityQueue<>();
            for(int i=0; i<n; i++){
                minHeap.add(fr.ni());
            }
            long sum = 0;
            while(max-->0 && !minHeap.isEmpty()){
                if(minHeap.peek() > 0)
                    break;
                sum += Math.abs(minHeap.poll());
            }
            System.out.println(sum);
        }
    }

    static class Helper {
        public int[] ipArrInt(int n) {
            int[] arr = new int[n];
            for (int i = 0; i < n; i++)
                arr[i] = fr.ni();
            return arr;
        }

        public long[] ipArrLong(int n, int si) {
            long[] arr = new long[n];
            for (int i = si; i < n; i++)
                arr[i] = fr.nl();
            return arr;
        }
    }

    static class FastReader {
        public BufferedReader reader;
        public StringTokenizer tokenizer;
        private static PrintWriter pw;

        public FastReader() {
            reader = new BufferedReader(new InputStreamReader(System.in));
            pw = new PrintWriter(System.out);
            tokenizer = null;
        }

        public String next() {
            while (tokenizer == null || !tokenizer.hasMoreTokens()) {
                try {
                    tokenizer = new StringTokenizer(reader.readLine());
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
            }
            return tokenizer.nextToken();
        }

        public int ni() {
            return Integer.parseInt(next());
        }

        public long nl() {
            return Long.parseLong(next());
        }

        public String rl() {
            try {
                return reader.readLine();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return null;
        }

        public int[] nextIntArr(int n) throws IOException {
            int[] arr = new int[n];
            for (int i = 0; i < arr.length; i++)
                arr[i] = fr.ni();
            return arr;
        }

        public void print(String str) {
            pw.print(str);
            pw.flush();
        }
    }
}