#include <fstream>

using namespace std;
ifstream cin("transport.in");
ofstream cout("transport.out");
int v[16001],n,k;
bool ok(int c)
{
    int i,tr,sc;
    sc=tr=0;
    for(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))
        {
            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+=v[i];
    }
    cout << bs_left (0,s);

    return 0;
}