//#include <iostream>
#include <fstream>
using namespace std;
ifstream cin("transport.in");
ofstream cout("transport.out");
long long st, ma, dr, mij, n, i,v[25600000],k;
 int f(int cap)
{
    int  in = 0, tr = 1;
    for(i = 1; i <= n ; i ++)
    {
        in += v[i];
        if(in > cap)
        {
            tr ++;
            in = v[i];
        }
    }
    return tr;

}
int main()
{
    // st = 1; dr = 256000000;
    cin >> n >> k;
    for(i =1 ; i<= n ;i ++ )
    {
        cin >>v[i];
        if (v[i] > ma)
            ma = v[i];

    }
    st = ma;
    dr = 256000000;
    while(st < dr)
    {
        mij = (st + dr) / 2;
        if(f(mij) <= k)
        {
            dr = mij;
        }
        else
        {
            st = mij +1;
        }
    }
    cout << st << endl;
    return 0;
}