import java.util.*;
public class Main{
	public static void main(String[] args){
		Scanner scan = new Scanner(System.in);
		int n = Integer.parseInt(scan.next());
		int k = Integer.parseInt(scan.next());
		int[] a = new int[n];
		for(int i = 0;i < n; ++i){
			a[i] = Integer.parseInt(scan.next());
		}
		Arrays.sort(a);
		int ans = a[n-1];
		for(int i = n-2; i >= n-k ; --i){
			if(a[i] >0){
				ans += a[i];
			}
		}
		System.out.println(ans);
	}
}