#include <bits/stdc++.h>

using namespace std;

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

void usain_bolt()
{
    ios::sync_with_stdio(false);
    fin.tie(0);
}

const int N = 2e4 + 5;

int a[N];

int main()
{
    usain_bolt();

    int n, k, mn = 2e9;

    fin >> n >> k;
    for (int i = 1; i <= n; ++i)
        fin >> a[i];
    int left = 1, right = 2e9;
    while (left <= right) {
        int mid = (left + right) >> 1;
        int cnt = 1, sum = 0;
        bool ok = true;
        for (int i = 1; i <= n && ok == true; ++i) {
            if (a[i] > mid) {
                ok = false;
                break;
            }
            sum += a[i];
            if (sum > mid) ++cnt, sum = a[i];
        }
        if (cnt <= k && ok == true) {
            mn = min(mn, mid);
            right = mid - 1;
        }
        else {
            left = mid + 1;
        }
    }
    fout << mn;
    return 0;
}