#include <iostream>
#include <algorithm>
#include <vector>
using namespace std;

int main() {
    int n, k;cin >> n >> k;
    vector <int> A(n);
    int ans = 0;
    for (int i=0;i < n; i++){
        cin >> A[i];
    }

    sort(A.begin(), A.end(), greater<int>());
    
    for (int i=0; i < k; i++){
        if (A[0] < 0){
            ans = A[0]; break;
        }
        else if (A[i] < 0)
            break;
        ans += A[i];
    }
    cout << ans << '\n';
}