#include <fstream>
#include <algorithm>
using namespace std;
ifstream fin("transport.in");
ofstream fout("transport.out");
int n, v[16001],i,st,dr,mij,bs,tv[16001],drum,k,sum;
int main()
{
    fin>>n>>k;
    for(i=1;i<=n;i++){
        fin>>v[i];
        sum+=v[i];
    }
    st=1;
    dr=sum;
    for(i=0;i<=sum;i++)
        tv[i]=i;
    while(st<=dr)
    {
        mij=(st+dr)/2;
        //fout<<mij<<endl;
        bs=0;
        drum=0;
        for(i=1;i<=n && drum<=k;i++)
        {
            bs+=v[i];
            if(bs>tv[mij])
            {
                //fout<<bs<<" ";
                drum++;
                bs=0;
                if(v[i]<=tv[mij])
                    i--;
            }
        }
        if(bs!=0)
        {
            bs=0;
            drum++;
        }
        //fout<<drum<<endl;
        if(drum<k)
            dr=mij-1;
        else
            if(drum>k)
                st=mij+1;
            else
                break;
    }
    fout<<mij;
    return 0;
}