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

#define ll long long
#define rep(i, n) for (int i = 0; i < (n); i++)
#define P pair<int, int>

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


}