Ali Tofigh wrote:
Is there any guarantee that Vertex descriptors are some kind of integers?
I don't think it's written anywhere, however if this is ever to change, I'm sure a lot of users will be upset, so it's not likely to change ;-)
In the examples provided add_edge is called with integers as vertex descriptors. Does the choice of parameters for the adjacency_list graph make a difference on this issue? E.g. whether the we choose vecS or listS as VertexList?
Yes. vertex_descriptor is integer only for vecS.
If future flexibility of the program being written is a factor (e.g. if we want it to be easy to change the definition of the graphs without necessarily changing other parts of the code) is it better to use add_vertex, followed by add_edge using the vertex descriptors returned by add_vertex?
Yes. It always better to use vertex_descriptor for any real code which is going to be used for arbitrary kind of graph. - Volodya