#include <fstream>

using namespace std;

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

int delivery ( int nr );

int n, k;

int v[16137];

int st, dr, mid;

int main()
{
    in >> n >> k;
    for ( register int i = 1 ; i <= n ; ++i )
        in >> v[i];
    st = 1;
    dr = 256000000;
    while ( st <= dr )
    {
        mid = ( st + dr ) / 2;
        if ( delivery (mid) <= k )
            dr = mid - 1;
        else
            st = mid + 1;
    }
    out << st;
    return 0;
}

int delivery ( int nr )
{
    int s = 0;
    int trans = 0;
    for ( register int i = 1 ; i <= n ; ++i )
    {
        if ( v[i] >= nr )
            return k + 1;
        if ( s + v[i] <= nr )
            s += v[i];
        else
        {
            ++trans;
            s = 0;
        }
    }
    return trans;
}