[Boost-users] [BGL] Inverting the map from strong_connected

From: John Krajewski (johnnyk1_at_[hidden])
Date: 2006-05-01 07:03:40

Hi all,
The function "strong_components" produces a mapping from vertex to 
component - but what I need is a mapping the other way, from component to 
vertex!

Now of course I could go through the property_map, query each vertex, and 
create the new map myself, but theres got to be a better way.  The map is 
just a writable_property_map concept, so theoretically I should be able to 
create my own somehow that will swap the key and value, but I'm not sure how 
I would do that.  Any suggestions?

I also want to create a graph of the strongly connected components, but I 
suppose theres no tricky way to do this - just go through each vertex in the 
returned map and add its connections to the strong component's connections 
(though there's probably something tricky I could do with iterators to make 
this automatic)

Thanks for any help, my mind is still adjusting to being warped by this 
generic programming stuff :)