#include<bits/stdc++.h>
using namespace std;
ifstream fin("transport.in");
ofstream fout("transport.out");

int n, v[200005], k, sum[200005];

int verif(int poz)
{
    int curr_sum = 0, ans = 1;
    for (int i = 1; i <= n; i++) {
        if (curr_sum + v[i] <= poz)
            curr_sum += v[i];
        else {
            curr_sum = v[i];
            ans++;
        }
    }

    return ans;
}

int main()
{
    fin >> n >> k;
    for (int i = 1; i <= n; i++) {
        fin >> v[i];
    }

    int st = 1, dr = 99999999, poz = 99999999 + 1;
    while (st <= dr) {
        int mijl = (st + dr) / 2;
        if (verif(mijl) <= k) {
            dr = mijl - 1;
            poz = mijl;
        } else {
           st = mijl + 1;
        }
    }

    fout << poz;
    return 0;
}