#include <bits/stdc++.h>
#define MODNum 1000000007
#define REP(type, i, a, b) for( type i = a; i < b; i++ )
typedef long long ll;

using namespace std;

int main (void) {
    int N, K, ans;
    cin >> N >> K;
    vector<int> A(N);
    REP(int,i,0,N) cin >> A.at(i);
    sort(A.begin(),A.end(),greater<int>());
    ans = A.at(0);
    REP(int,i,1,K){
        if ( A.at(i) <= 0 ) break;
        else ans += A.at(i);
    }
    cout << ans << endl;
    return 0;
}