// yukicoder No.1046
#include <bits/stdc++.h>
using namespace std;

int main()
{
  int n, k; cin >> n >> k;

  vector<int> vec(n);
  for(int i = 0; i < n; ++i) cin >> vec[i];

  sort(vec.rbegin(), vec.rend());
  int sum = vec[0];
  for(int i = 1; i < k; ++i) {
    if(vec[i] > 0) sum += vec[i];
    else break;
  }

  cout << sum << "\n";
  return 0;
  
}