#include<iostream>
#include<vector>
#include<algorithm>
typedef long long ll;
using namespace std;


int main(void){
    int n,k;
    cin>>n>>k;
    vector<int>a(n);
    for(int i=0;i<n;i++)cin>>a[i];
    int ans = 0;
    sort(a.begin(),a.end(),greater<int>());
    bool flag = false;
    for(int i=0;i<k;i++){
        if(a[i]>=0){
            ans+=a[i];
            flag = true;
        }
        else continue;
    }
    if(flag)cout<<ans<<endl;
    else cout<<a[0]<<endl;
    return 0;
}