#include <bits/stdc++.h>

using namespace std;

int salt[16005];

int main()
{
    ifstream fin("transport.in");
    ofstream fout("transport.out");
    int n, k;
    fin >> n >> k;
    for(int i = 1; i <= n; ++i)
        fin >> salt[i];
    long long rez = 0, pas = 1LL << 60;
    while(pas){
        long long sum = 0;
        int cnt = 1;
        for(int i = 1; i <= n; ++i){
            if(sum + salt[i] <= rez + pas)
                sum += salt[i];
            else{
                sum = 1LL * salt[i];
                cnt++;
            }
        }
        if(cnt > k)
            rez += pas;
        pas /= 2;
    }
    fout << rez + 1;
    return 0;
}