#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;
int ans;
    while ( st <= dr )
    {
        mid = ( st + dr ) / 2;
        if ( delivery (mid) <= k )
            dr = mid - 1;
        else
            ans=mid,st = mid + 1;
    }
    out << ans;
    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 = v[i];
        }
    }
    return trans + 1;
}