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Hi,

I'd like to find vertices of convex hull of points in arbitrary dimension 
using
Convex_hull_d. I just tried the 9 points of square centered at the origin.
Obviously, I should get 4 points, but I'm getting 8. Any thought?
Here goes the code that I tried.

Thanks,

#include <iostream>
#include <vector>

#include <CGAL/Cartesian.h>
#include <CGAL/Convex_hull_d.h>
#include <CGAL/Cartesian_d.h>

using namespace std;
using namespace CGAL;

int main()
{

        Convex_hull_d< Cartesian_d<double> > A(2);

        vector< vector<int> > V;
        vector<int> vi(DIM);

        vi[0]=-1; vi[1]=1; V.push_back(vi);
        vi[0]=0; vi[1]=1; V.push_back(vi);
        vi[0]=1; vi[1]=1; V.push_back(vi);

        vi[0]=-1; vi[1]=0; V.push_back(vi);
        vi[0]=0; vi[1]=0; V.push_back(vi);
        vi[0]=1; vi[1]=0; V.push_back(vi);

        vi[0]=-1; vi[1]=-1; V.push_back(vi);
        vi[0]=0; vi[1]=-1; V.push_back(vi);
        vi[0]=1; vi[1]=-1; V.push_back(vi);

        for( vector< vector<int> >::iterator it=V.begin(); it!=V.end(); it++ 
){
                Point_d< Cartesian_d<double> >
pot(DIM,(*it).begin(),(*it).end());
                A.insert(pot);
        }

        for( Convex_hull_d< Cartesian_d<double> >::Hull_vertex_iterator
it=A.hull_vertices_begin() ; it!=A.hull_vertices_end(); it++ )
                cout << A.associated_point(it) << endl;

        return 0;
}