Re: [Boost-users] [BGL] premature termination in dijkstra using visitor

Subject: Re: [Boost-users] [BGL] premature termination in dijkstra using visitor
From: Ralf Goertz (R_Goertz_at_[hidden])
Date: 2009-10-05 04:57:14

Ralf Goertz wrote:

> Hi,
> 
> I have some very large undirected graphs (half a million vertices).
> Edges have weight 0 or 1. For each vertex I need to find all vertices
> 
>         * that are in sum 2 edges away
>         * whose distance is 0
> 
> Both tasks can be done with breadth-first searches but I don't know in
> advance how many edges in depth I have to traverse. That's why I
> thought of Dijkstra's algorithm. But in my case this is overkill as I
> am not interested in the exact distance of a vertex from a given vertex
> but only in if it is not farther than 0 or 2 away. Is it possible to
> use a visitor to alter the colormap to mark vertices as final that are
> too far even thought they are not final yet?
> 
> Ralf

Thank you for your suggestions. However, I'm afraid I need some more
help. I can't figure out at what event I need to intercept and how I get
the current distance. I must admit that BGL is quite a challenging
library. It seems, generality comes at a high price.

Ralf