#include <fstream>
#define NMAX 16020

using namespace std;

ifstream in("transport.in");
ofstream out("transport.out");

int n,k;
int v[NMAX];
int suma=0,vmax=0,nrtrans=0,maxim;
int primul,ultimul,mij;

int main()
{

    in>>n>>k;
    for(int i=1; i<=n; i++)
    {
        in>>v[i];
        suma+=v[i];
        if(v[i]>maxim) maxim=v[i];
    }
    primul=maxim;
    ultimul=suma;
    while(primul<=ultimul)
    {
        mij=(primul+ultimul)/2;
        vmax=mij;
        nrtrans=1;
        vmax=vmax-v[1];
        for(int i=2; i<=n; i++)
        {
            if(vmax>=v[i]) vmax=vmax-v[i];
            else
            {
                nrtrans++;
                vmax=mij-v[i];
            }
        }
        if(nrtrans<=k) ultimul=mij-1;
        else primul=mij+1;
    }

    out<<primul;

    in.close();
    out.close();
    return 0;

}