{
  my %seen;
  sub track {
	my $last=$_[-1];
	$seen{$last}=1;
 
	for my $next (@{$graph{$last}}) {
	  next if $seen{$next};
	  if ($next eq $stop) {
	    #print join ("->",@_,$stop),"\n";
	    $anzahl++;
	    print "$anzahl at ",time-$time0,"\n" if $anzahl%10000==0;
	  } else {
		track(@_,$next);
	  }  
	}
	delete $seen{$last};
  }
}