int main() {
    Polyhedron P;
    Build_triangle<HalfedgeDS> triangle;
    P.delegate( triangle);
    CGAL_assertion( P.is_triangle( P.halfedges_begin()));
    return 0;
}
int main() {
    Polyhedron P;
    Build_triangle<HalfedgeDS> triangle;
    P.delegate( triangle);
    CGAL_assertion( P.is_triangle( P.halfedges_begin()));
    
    CGAL::set_pretty_mode(std::cout);
    
    std::cout << "Success creating two triangles: "
                  << std::endl;
    
    std::cout << "The polyhedron created at this stage" << P << std::endl;
    
    running_iterators(P);

    return 0;
}