#include <fstream>
using namespace std;

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

int main()
{
    int n, k, mattress[16000];
    fin >> n >> k;
    //fout << n << ' ' << k << endl;
    for (int i = 0; i < n; i++)
    {
        fin >> mattress[i];
        //fout << saltele[i] << endl;
    }

    int biggestMattress = 0, sumOfMattresses = 0;
    for (int i = 0; i < n; i++)
    {
        if (mattress[i] > biggestMattress)
            biggestMattress = mattress[i];
        sumOfMattresses += mattress[i];
    }
    //fout << "biggestMattress=" << biggestMattress<< ' '
    //    << "sumOfMatresses=" << sumOfMattresses<<endl;

    int distribution[16000], sum, volume, solutionFound = 0, transportNo;

    distribution[0] = 1; // first mattress in the first transport

    int left = biggestMattress, right = sumOfMattresses;

    volume = (left + right) / 2;

    while (left < right)
    {
        transportNo = 1;
        sum = mattress[0];
        //fout<<volume<< ' '<<endl; 
        for (int i = 1; i < n; i++)
        {
            if (sum + mattress[i] <= volume)
            {
                sum += mattress[i];
                distribution[i] = transportNo;
            }
            else
            {
                transportNo++;
                sum = mattress[i];
                distribution[i] = transportNo;
            }

            if (transportNo > k)
            {
                left = volume + 1;
                volume = left + (right - left) / 2;
                break;
            }
            else
            {
                if (i == n - 1)
                {
                   right = volume - 1;
                   volume = left + (right - left) / 2;
                   break;
                }
            }
        }
    }
    fout << left;
    return 0;
}