#include <iostream>
#include <vector>
#include <string>
#include <algorithm>
#include <cstdio>
#include <cstring>
#include <cmath>
using namespace std;
using ll = long long;

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 s = 0;
    for (int i = 0; i < k; i++) {
        int t = a[n - 1 - i];
        if (i > 0 && t <= 0) break;
        s += t;
    }

    cout << s << endl;

    return 0;
}