#include <fstream>
using namespace std;
int n,k,v[16000],cs,cd,l1,l2,l;
bool t,t2;
void bin(int l);
ifstream fin ("fisier.in");
ofstream fout("fisier.out");
int main ()
{

    fin>>n>>k;
    for(int i=0; i<n; ++i)
    {
        fin>>v[i];
        cd+=v[i];
        cs=max(v[i],cs);
    }
    l=(cs+cd)/2;
    bin(l);
}
void bin(int l)
{
    int s=v[0],drum=1;
    for(int i=1; i<n; ++i)
    {
        if(v[i]+s<=l)s+=v[i];
        else
        {
            drum++;
            s=v[i];
            if(drum>k)
            {
                l2=l1;
                l1=l;
                t2=t;
                t=0;
                if(t2==1&&l2==1+l1)
                {
                    fout<<l2;
                    return;
                }
                cs=(cs+cd)/2;
                l=(cs+cd+2)/2;
                bin(l);
            }
        }
    }
    l2=l1;
    l1=l;
    t2=t;
    t=1;
    if(t2==0&&l1-l2==1)
    {
        fout<<l;
        return;
    }
    cd=(cd+cs)/2;
    l=(cs+cd)/2;
    bin(l);
}