import java.util.*;

public class Main {
    public static void main(String args[]) throws Exception {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int k = sc.nextInt();
        int max = Integer.MIN_VALUE;
        PriorityQueue<Integer> pq = new PriorityQueue<>();
        for(int i = 0; i < n; i++) {
        	int num = sc.nextInt();
        	max = Math.max(max, num);
        	if(num > 0)
        		pq.offer(num);
        	if(pq.size() > k) pq.poll();
        }
        int sum = 0;
        while(!pq.isEmpty())
        	sum += pq.poll();
        System.out.println(sum == 0 ? max : sum);
    }
}