AdjacencyRec adj = new AdjacencyRec(curNode, prevAdj);
queue.insertAndGrow(adj);
prevAdj = adj;
}
while(queue.size >= threshold) {
AdjacencyRec rec = (AdjacencyRec)queue.pop();
if (rec.dirty) {
rec.dirty = false;
queue.insert(rec);
} else {
rec.node1.addAll(rec.node2);