#include <bits/stdc++.h>
using namespace std;


int main()
{
    ifstream in("transport.in");
    ofstream out("transport.out");

    int n, k;
    in >> n >> k;

    vector <int> v(n);
    for (auto & i : v)
        in >> i;

    auto verif = [&](int dim) -> bool {
        int need = 0, last = 0;
        for (auto i : v) {
            if (i > last)
                need++, last = dim;
            last -= i;
            if (last < 0)
                return false;
        }

        return need <= k;
    };

    int ans = 0;
    for (int pas = (1 << 30); pas; pas /= 2)
        if (!verif(ans + pas))
            ans += pas;
    
    out << ans + 1 << '\n';

    return 0;
}