#include <fstream>

using namespace std;

ifstream cin("transport.in");
ofstream cout("transport.out");;

int v[16001];

int main()
{
    int st,dr,n,sol,s,i,m,nrt,k;
    cin>>n>>k;
    st=-1;
    dr=0;
    for(i=1;i<=n;i++)
    {
        cin>>v[i];;
        if(v[i]>st)
            st=v[i];
        dr+=v[i];
    }
    sol=-1;
    while(st<=dr)
    {
        m=(st+dr)/2;;
        nrt=0;
        s=0;
        for(i=1;i<=n;i++)
        {
            if(s+v[i]<=m)
                s+=v[i];
            else
            {
                s=v[i];
                nrt++;
            }
        }
        if(nrt>k)
            st=m+1;
        else
        {
            sol=m;
            dr=m-1;
        }
    }
    cout<<sol;
    return 0;
}