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

int main() {
  int N, K;
  cin >> N >> K;
  vector<int> A(N);
  for (int i = 0; i < N; i++) cin >> A.at(i);
  sort(A.rbegin(), A.rend());
  int ans = 0, cnt = 0;
  for (int i = 0; i < N && cnt < K; i++) {
    if (A.at(i) < 0) continue;
    ans += A.at(i), cnt++;
  }
  cout << ((cnt) ? ans : A.at(0)) << "\n";
}