#include<iostream>
#include<string>
#include<algorithm>
#include<cctype>
#include<set>
#include<bitset>
#include<math.h>
#include<map>
#include<queue>
#include<iomanip>
using namespace std;

int main(){
    int n, k, sum1 = 0;
    cin >> n >> k;
    vector<int> a(n);
    for (int i = 0; i < n; i++) cin >> a[i];
    sort(a.begin(), a.end(), greater());
    for (int i = 0; i < k; i++){
        if(a[i] > 0) sum1 += a[i];
        else break;
    }
    cout << sum1 << endl;
}