#include <fstream>

using namespace std;
ifstream cin("transport.in");
ofstream cout("transport.out");
const int N=16005;
int n,k;
int v[N];
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 max1=0,s=0,i;
    cin>>n>>k;
    for(i=1;i<=n;i++)
    {
        cin>>v[i];
        max1=max(max1,v[i]);
        s=s+v[i];
    }
    cout<<bs_left(max1,s);
    return 0;
}