#include <cstdio>
#include <cstring>
#include <cmath>
#include <utility>
#include <iostream>
#include <functional>
#include <bitset>
#include <algorithm>
#include <vector>
#include <forward_list>
#include <set>
#include <map>
#include <queue>
#include <deque>
#include <stack>
#include <numeric>
#define ll long long int
#define rep(i,n) for(int i=0;i<(n);i++)
using namespace std;

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