Your problem in a nutshell is Breadth First Traversal.

Here is a bit of perly pseudo code that perhaps you will find useful.

# the fact that the below looks like perl should not be 
# taken a sign that it is perl. It certainly ain't tested perl
sub getlinks {
      my $rootpage=shift;
      my (@queue,%seen,%visited)=($rootpage);
      $seen{$rootpage}++;
      while (@queue) {
         my $this_page=shift @queue;

         # dont revisit this page
         next if $visited{$this_page}++; 

         my @found=get_all_links_from_page($this_page);
         !$seen{$_}++ && !visited{$_} && push @queue,$_
              foreach @found;

         # additional post processing of link
      }
      return $results_of_postprocessing
}
[download]

BTW this is the basic structure of a breadth first traversal of an arbitrary data structure. You might want to research the subject a bit on your own...

HTH

Yves / DeMerphq
---
Writing a good benchmark isnt as easy as it might look.