beginner/VTK_marching Cube_vertices and faces/

Hi I would like to know how can I get the coorinates of vertices and the face after marching cube

vtkSmartPointer<vtkMarchingCubes> surface =
    vtkSmartPointer<vtkMarchingCubes>::New();
surface->SetInputData(imageData);
surface->ComputeNormalsOn();

I would like to know how can I see the values of marching cube results? how can I access the coordinates of vertices and the faces?

Thank you