#include <iostream>
#include <fstream>

using namespace std;

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

long long s, maxi, n, k;
int v[20000];

int vf( int x )
{
    int nr = 0;
    int sum = 0;
    for( int i = 1; i <= n; i ++ )
    {
        if( sum + v[i] <= x )
            sum += v[i];
        else
        {
            nr++;
            sum = v[i];
        }
    }
    return nr+1;
}

int cbin( long long st, long long dr )
{
    long long rasp = 0 ;
    while( st <= dr )
    {
        long long mij = st + (dr - st)/2;

        if( vf(mij) <= k )
        {
            rasp = mij;
            dr = mij - 1;
        }
        else
            st = mij + 1;
    }

    return rasp;
}

int main()
{
    f >> n >> k;

    for( int i = 1; i <= n; i++ )
    {
        f >> v[i];
        s += v[i];
        if( v[i] > maxi )
            maxi = v[i];
    }

    g << cbin(maxi, s);

    return 0;
}