[boost] BGL - how to find end of predecessor chain?

From: jsiek_at_[hidden]
Date: 2000-10-15 13:19:52

Hi John,

In the case when using an adjacency_list with VertexList=vecS, you
could initialize the predecessor array to -1.

In the case when using an adjacency_list with VertexList=listS, you
could initialize the predecessor array to 0 (null pointer).

Cheers,

Jeremy

John Britton writes:
 > After performing a BFS which fills in a vector of Vertex predecessors, how
 > do I determine whether a given Vertex has a valid predecessor? Comparing
 > against a default constructed Vertex doesn't seem to work since the default
 > constructed Vertex apparently has an index of 0, and thus cannot be
 > differentiated from vertex( 0, G ).
 > Thanks,
 > John Britton
 > Very Important Engineer++
 > Peak Audio Inc.
 > 1790 30th Street, Suite 414
 > Boulder, CO 80301
 > 303.449.9337 x102
 > johnb_at_[hidden]
 > http://www.peakaudio.com/
 > 
 > 
 > 
 > 
 >