#include <fstream>
#include <deque>

using namespace std;

deque <int> coada;
int v[5000001];

ifstream fin ("deque.in");
ofstream fout ("deque.out");

int main()
{
    int n, k, suma = 0;
    fin>>n>>k;
    for ( int i = 1; i <= n; ++i )
        fin>>v[i];
    for ( int i = 1; i <= n; ++i )
    {
        if ( coada.empty() == 1 )
            coada.push_back(v[i]);
        else
        {
            if ( coada.size() == k )
            {
                suma += coada.front();
                coada.pop_front();
            }
            if ( coada.front() >= v[i] )
                coada.push_front(v[i]);
            else
            {
                if ( coada.back () > v[i] )
                    coada.pop_back();
                else
                    coada.push_back(v[i]);
            }
        }
    }
    fout<<suma;
}