#include <fstream>

using namespace std;

ifstream cin("transport.in");
ofstream cout("transport.out");

int n, k, v[16005];

bool ok(int c){
    int i, tr, sc;
    sc = tr = 0;
    for(int i = 1; i <= n; i ++){
        if(v[i] > c) { return 0; }
        if(sc + v[i] <= c){
            sc = sc + v[i];
        }
        else { tr ++; sc = v[i]; }
    }
    if(sc > 0){ tr ++; }
    return tr <= k;
}

int bs_left(int st, int dr){
    int med, last = -1;
    while(st <= dr){
        med = (st + dr) / 2;
        if(ok(med) > 0){
            last = med;
            dr = med - 1;
        }
        else {
            st = med + 1;
        }
    }
    return last;
}

int main()
{
    int s = 0;
    cin >> n >> k;
    for(int i = 1; i <= n; i ++){
        cin >> v[i];
        s = s + v[i];
    }
    cout << bs_left(1, s);
    return 0;
}