#include <fstream>
#include <algorithm>
using namespace std;
ifstream fin ("transport.in");
ofstream fout ("transport.out");
const int NMAX=16005;
int v[NMAX],k,n;
bool ok (int c)
{
    int tr=0,i,sc=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(int st,int dr)
{
    int last=-1,med;
    while(st<=dr)
    {
        med=(st+dr)/2;
        if(ok(med))
            {
                last=med;
                dr=med-1;
            }
        else
            st=med+1;
    }
    return last;
}
int main()
{
    int i,s,ans;
    fin>>n>>k;
    for (i=1;i<=n;i++)
    {
        fin>>v[i];
        s=s+v[i];
    }
    ans=bs(1,s);
    fout<<ans<<"\n";
    fin.close();
    fout.close();
    return 0;
}