#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[i];
  sort(a.begin(), a.end());
  int sum = 0;
  for (int i = 0; i < k; i++) {
    if (a[i] <= 0) {
      if (i == 0) sum += a[i];
      break;
    }
    sum += a[i];
  }
  cout << sum << endl;
  return 0;
}