/*
infoarena.ro/problema/transport
*/
#include<fstream>
using namespace std;
ifstream fin("transport.in");
ofstream fout("transport.out");

    short int v[160005],n,k;

bool check(int x)
{
    int c=0,s=0,i;
    for(i=1;i<=n&&c<=k;i++)
    {
        if(s+v[i]<=x)
            s+=v[i];
        else
        {
            s=v[i];
            c++;
        }
    }
    c++;
    if(c<=k)
        return 1;
    else
        return 0;
}

int main()
{
    int i;
    fin>>n>>k;
    for(i=1;i<=n;i++)
        fin>>v[i];
    int l=1,r=257000000,mid,sol;
    while(l<=r)
    {
        mid=(l+r)/2;
        if(check(mid))
        {
            //fout<<check(mid)<<" "<<mid<<endl;
            sol=mid;
            r=mid-1;
        }
        else
            l=mid+1;
    }
    fout<<sol<<'\n';



    fin.close();
    fout.close();
    return 0;
}