[Boost-users] How to find ancestor nodes in a graph, thanks

From: sean yang (seanatpurdue_at_[hidden])
Date: 2006-07-04 19:49:46

Hi folks,

I want to find all the nodes that can reach a specific node 'target_n'. 
Let's say, an example graph looks like this:
G= (V, E), where
V={A, B, C, target_1, target_2, D, E, F}, and
E= {
(A-->B),
(B-->target_1),
(C-->target_2),
(A-->target_2),

(D-->E),
(E-->F),
(F-->D),
}
In this example, I want to find out(say print them out) 'A', 'B', 'C'.

Now, I have a graph representation like the following one .
------------------------------
typedef adjacency_list<vecS, vecS, bidirectionalS,
               VertexNameProperty > Graph;
Graph travel;
---------------------------------
And I have already read in the above information to the Graph travel. One 
way I am thinking of to achieve the above goal is: reverse the direction of 
edges in G, i.e., getting a G', first; and then do BFS from target_n nodes.

My question is: (1) is there an easy (some API, sorry I am not familar with 
the library) way to reverse edge direction? (2) is there an easy way to add 
a 'printf()' during BFS?

Thanks,
Sean

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