#include<bits/stdc++.h>
using namespace std;
using ll = long long;

int main()
{
	int n,k;
	cin >> n >> k;
	vector<int> A(n);
	for(int i = 0;i<n;i++)cin >> A[i];
	sort(A.begin(),A.end(),greater<int>());
	int sum = 0;
	for(int i = 0;i<k;i++)
	{
		if(i==0){sum += A[i];continue;}
		if(A[i]>0)sum += A[i];
	}
	cout<<sum<<endl;
}