#include <fstream>

using namespace std;
int n,k,v[16005];
ifstream in("transport.in")
ofstream out("transport.out");
int ok(int med)
{
    int i,tr,sc;
    sc=tr=0;
    for(i=1;i<=n;i++)
    {
        if(v[i]>med)
            return 0;
        if(sc+v[i]<=med)
            sc=sc+v[i];
        else
        {
            tr++;
            sc=v[i];
        }
    }
    if(sc>0)
        tr++;
    if(tr<=k)
        return 1;
    return 0;
}
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 dr=0,i,st=1,trans;
    cin>>n>>k;
    for(i=1;i<=n;i++)
    {
        cin>>v[i];
        dr=dr+v[i];
    }
    trans=bs_left(st,dr);
    cout<<trans;
    return 0;
}