#include <bits/stdc++.h>
#define rep(i,n) for(int i = 0;i < (n);i++)
using namespace std;
using ll = long long;
using pii = pair<int,int>;

int main(){
    int n,k;
    cin >> n >> k;
    vector<int> a(n);
    rep(i,n) cin >> a[i];
    sort(a.rbegin(),a.rend());
    int sum = 0;
    rep(i,k){
        if(a[i] > 0)sum += a[i];
    }
    cout << sum << endl;
}