#include <iostream>
#include <fstream>
using namespace std;
ifstream in("transport.in");
ofstream out("transport.out");
const int MAX = 16000;
const int dreapta = MAX*MAX;
int n, k, v[MAX+1];
bool mergee (int l)
{
    int s=0,cnt=0;
    for(int i=0; i<n; ++i)
    {
        s=s+v[i];
        if(s>l)
        {
            cnt++;
            s=v[i];
        }
    }
    cnt++;
    if(cnt<=k)
        return 1;
    return 0;
}

int cautbin (int dr)
{
    dr=dreapta;
    int st=1, mij, res=-1;
    while(st<=dr)
    {
        mij=(st+dr)/2;
        if( mergee(mij) )
        {
            res=mij;
            dr=mij-1;
        }
        else
            st=mij+1;
    }
    return res;
}

int main()
{
    in>>n>>k;
    int suma=0;
    for(int i=0; i<n; ++i)
    {
        in>>v[i];
        suma=suma+v[i];
    }
    //cout << mergee(7) << '\n';
    out<<cautbin(dreapta);
    return 0;
}