#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define endl "\n"
#define rep(i, a, n) for (int i = a; i < n; ++i)

int main() {
    int n, k;
    cin >> n >> k;
    vector<int> a(n);
    rep(i, 0, n) cin >> a[i];

    sort(a.begin(), a.end());
    reverse(a.begin(), a.end());
    int ans = 0;
    rep(i, 0, k) {
        if (a[i] > 0) ans += a[i];
    }
    cout << ans << endl;

    return 0;
}