#include <fstream>

using namespace std;
ifstream fin("transport.in");
ofstream fout("transport.out");
const int M=16005;
int n,k,v[M],val;
bool ok(int med)
{
    int i,sc,nrtr;
    sc=nrtr=0;
    for(i=1;i<=n;i++)
    {
        if(v[i]>med)
            return 0;
        if(sc+v[i]<=med)
            sc=sc+v[i];
        else
        {
            nrtr++;
            sc=v[i];
        }
    }
    nrtr++;
    return(nrtr<=k);
}
int bsL(int st,int dr)
{
    int med,last;
    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 s=0,i;
    fin>>n>>k;
    for(i=1;i<=n;i++)
    {
        fin>>v[i];
        s=s+v[i];
    }
    val=bsL(1,s);
    fout<<val;
    return 0;
}