#include <iostream>
#include <fstream>
#define nmax 16001

using namespace std;
ifstream f("transport.in");
ofstream g("transport.out");

int v[nmax], maxCamion, sumaMomentana, kMomentan, minCamion, limitL, limitR, sMax, ok, intMaxCamion;
int main()
{
    int n, k;
    f >> n >> k;
    for (int i = 1; i <= n; i++) {
        f >> v[i];
        if (minCamion < v[i]) minCamion = v[i];
        sMax += v[i];
    }
    maxCamion = (sMax + minCamion) / 2;
    limitL = minCamion;
    limitR = sMax;
    while (1) {
        for (int i = 1; i <= n; i++) {
            sumaMomentana += v[i];
            if (sumaMomentana > maxCamion) {
                kMomentan++;
                sumaMomentana = v[i];
                if (i == n) kMomentan++;
            }
            else if (i == n) kMomentan++;
        }
        if (kMomentan > k) {
            limitL = maxCamion;
            maxCamion = (limitL + limitR) / 2;
            intMaxCamion = (int) (limitL + limitR) / 2;
        }
        if (kMomentan <= k) {
            limitR = maxCamion;
            maxCamion = (limitL + limitR) / 2;
            intMaxCamion = (int) (limitL + limitR) / 2;
        }
        if (limitL + 1 == limitR) {
            if (intMaxCamion > maxCamion) g << limitL;
            else g << limitR;
            return 0;
        }
        sumaMomentana = 0;
        kMomentan = 0;
    }
    return 0;
}