#include <iostream>
#include <vector>
#include <algorithm>

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 ans = 0;
    for (int i=n-1; i>=n-k-1&&a[i]>0; i--)
        ans += a[i];

    cout << ans << endl;
}