Don't choke on apsp discrepancy for arch-isolated islands

diff --git a/yarrg/yppedia-chart-parser b/yarrg/yppedia-chart-parser
index 44a143b50c662bb6a4cc7c76cff7b98c7f44bc8a..4ce6bcecd36195da8061b9ff2cf93d0e7f983f3d 100755 (executable)
--- a/yarrg/yppedia-chart-parser
+++ b/yarrg/yppedia-chart-parser
@@ -494,6 +494,7 @@ END
 
     my $result= Graph::Undirected->new();
     foreach my $edge_ac ($g->edges()) {
+        $result->add_vertex($edge_ac->[0]); # just in case
         next if $edge_ac->[0] eq $edge_ac->[1];
        my $edgename_ac= join ' .. ', @$edge_ac;
        printf DEBUG "spr %s edge %s\n", $what, $edgename_ac;