#include <fstream>
#include <stdlib.h>
using namespace std;
int n,k,v[16000],cs,cd,l2,l;
bool t;
void bin(int cs,int cd);
ifstream fin ("transport.in");
ofstream fout("transport.out");
int main ()
{
    fin>>n>>k;
    for(int i=0; i<n; ++i)
    {
        fin>>v[i];
        cd+=v[i];
        cs=max(v[i],cs);
    }
    bin(cs,cd);
}
void bin(int cs, int cd)
{
    int s=v[0],drum=1;
    l=(cs+cd)/2;
    for(int i=1; i<n; ++i)
    {
        if(v[i]+s<=l)s+=v[i];
        else
        {
            drum++;
            s=v[i];
            if(drum>k)
            {
                if(t==1&&l2==1+l)
                {
                    fout<<l2;
                     exit (EXIT_SUCCESS);
                }
                l2=l;
                t=0;
                cs=(cs+cd)/2;
                bin(cs,cd);
            }
        }
    }
    if(t==0&&l-l2==1)
   {
        fout<<l<<" ";
        exit(EXIT_SUCCESS);
    }
    t=1;
    l2=l;
    cd=(cd+cs)/2;
    bin(cs,cd);
}