#include <iostream>
#include <fstream>
using namespace std;
const int NMAX=16000;
ifstream fin("transport.in");
ofstream fout("transport.out");
int v[NMAX+5];
int n,k;
bool ok(int c)      //c=capacitate
{
    int tr,i,sc;
    tr=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_left(int st,int dr)
{
    int mid,last=-1;
    while(st<=dr)
    {
        mid=st+(dr-st)/2;
        if(ok(mid))
        {
            last=mid;
            dr=mid-1;
        }
        else
            st=mid+1;
    }
    return last;
}
int main()
{
    int i,smax;
    smax=0;
    fin>>n>>k;
    for(i=1;i<=n;i++)
    {
        fin>>v[i];
        smax=smax+v[i];
    }
    fout<<bs_left(1,smax)<<"\n";
    fin.close();
    fout.close();
    return 0;
}