#include <stdio.h>

int main(void){
	int n = 0 , k = 0;
	scanf("%d %d",&n,&k);
	int fresh[n];
	for(int i = 0 ; i < n ; i ++){
		scanf("%d",&fresh[i]);
	}
	for(int i = 0 ; i < n ; i++){
		for(int j = i ; j < n ; j++ ){
			if(fresh[i] < fresh[j]){
				int num = fresh[i];
				fresh[i] = fresh[j];
				fresh[j] = num;
			}
		}
	}
	int delicious = 0;
	for(int i = 0 ; i < k ; i++){
		if(fresh[i] <= 0){
			break;
		}
		delicious += fresh[i];
	}
	printf("%d",delicious);
}