#include <fstream>
using namespace std;
ifstream in("transport.in");
ofstream out("transport.out");
const int N = 16000*16000+10;
int n,k,a[16001],st=1,dr=N,mij,i;
bool check_capacity(int c)
{
    int x=0,transporturi=0;
    for (int i=1; i<=n; ++i)
    {
        x+=a[i];
        if (x>c) transporturi++,x=a[i];
        else if (x==c) transporturi++,x=0;
    }
    if (x) transporturi++;
    if (transporturi<=k)
        return true;
    else
        return false;
}
int main()
{
    in>>n>>k;
    for (i=1; i<=n; ++i)
        in>>a[i];
    while (st<dr)
    {
        mij=(st+dr)/2;
        if (check_capacity(mij))
            dr=mij;
        else
            st=mij+1;
    }
    out<<dr<<"\n";
}