#include <iostream>
#include <fstream>

using namespace std;

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

long long st, dr, n, k, a[16003], piv, sum;

int main()
{
    ios::sync_with_stdio(0);
    fin.tie(0);
    fin >> n >> k;
    for(int i = 1; i <= n; i++) fin >> a[i];
    st = 1; dr = 100000000;
    while(st <= dr)
    {
             piv = st + (dr - st) / 2;
             //sum = 0;
             p = 0;
             for(int i = 1; i <= n; i++)
             {
                     sum = 0;
                     while(a[i] < (piv - sum) && i <= n)
                     {
                                sum += a[i];                                
                     }
                     p++;
             }
             if(p < k) dr = piv - 1;
             if(p > k) st = piv + 1;
    }
    fout << (st + dr) / 2;
    return 0;
}