// and mark as part of the paths any node that has a children which is already
// part of the path (or is dst itself).
func (po *poset) findpaths(cur, dst uint32) bitset {
	seen := newBitset(int(po.lastidx + 1))
	path := newBitset(int(po.lastidx + 1))
	path.Set(dst)
	po.findpaths1(cur, dst, seen, path)
	return path
}

func (po *poset) findpaths1(cur, dst uint32, seen bitset, path bitset) {
	if cur == dst {

	if edgeCount < g.destinationEdgeThreshold {
		delete(g.destinationEdgeIndex, n.ID())
		return
	}

	// get or create the index
	index := g.destinationEdgeIndex[n.ID()]
	if index == nil {
		index = newIntSet()
	} else {
		index.reset()
	}

	// populate the index
	g.graph.VisitFrom(n, func(dest graph.Node) bool {
		if destinationEdge, ok := g.graph.EdgeBetween(n, dest).(*destinationEdge); ok {