#include <bits/stdc++.h>

using namespace std;

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

int a[16005], n, k;

int main()
{
    int i, ssir, s, cap, nr, maxx;
    ssir = maxx = 0;
    fin >> n >> k;
    for(i = 1; i <= n; i++)
    {
        fin >> a[i];
        ssir += a[i];
        maxx = max(maxx, a[i]);
    }
    int st, dr, mij;
    st = maxx;
    dr = ssir;
    cap = -1;
    while(st <= dr)
    {
        s = 0;
        nr = 1;
        mij = (st + dr) / 2;
        for(int i = 1; i <= n; i++)
        {
            if(s + a[i] <= mij)
                s += a[i];
            else
            {
                nr++;
                s = a[i];
            }
        }
        if(nr <= k)
        {
            cap = mij;
            dr = mij - 1;
        }
        else
            st = mij + 1;
    }
    fout << cap;
    return 0;
}