private void konigDFS(Set<Vertex> konigSet, Vertex v, boolean edgesInMatch) {
if (!konigSet.contains(v)) {
konigSet.add(v);
for (Vertex neighb : v.getNeighbors()) {
if (neighb.getId() != SOURCE_ID && neighb.getId() != SINK_ID) {
if (edgesInMatch == (getFlow(v, neighb) > 0 || getFlow(neighb, v) > 0)) {
konigDFS(konigSet, neighb, !edgesInMatch);
}
}
}
}
}
private void computeMatchSet() {
for (Vertex v : LV) {
for (Vertex neighb : v.getNeighbors()) {
if (neighb.getId() != SOURCE_ID && getFlow(v, neighb) > 0) {
matches.add(v);
matches.add(neighb);
}
}
}
}
private void writeVertexProperties(Writer writer, Vertex e) throws IOException {
Object blueprintsId = e.getId();
if (!useId) {
writeKey(writer, vertexIdKey);
if (blueprintsId instanceof Number) {
writeNumberProperty(writer, (Number) blueprintsId);
} else {
writeStringProperty(writer, blueprintsId);
}
}
writeProperties(writer, e);
}
private void writeVerticies(Writer writer, List<Vertex> verticies, Map<Vertex, Integer> ids)
throws IOException {
int count = 1;
for (Vertex v : verticies) {
if (useId) {
Integer id = Integer.valueOf(v.getId().toString());
writeVertex(writer, v, id);
ids.put(v, id);
} else {
writeVertex(writer, v, count);
ids.put(v, count++);
}
}
}
// Uses Konig's theorem to compute min vertex cover
// Compute in both directions as the friend, may or may not appear in a
// particular vertex cover, depending on graph structure
private void computeInvitees() {
Set<Vertex> result;
Set<Vertex> minVertexCovers1 = computeMinVertexCover(LV, RV);
Set<Vertex> minVertexCovers2 = computeMinVertexCover(RV, LV);
if (minVertexCovers1.contains(friend)) {
result = minVertexCovers1;
} else {
result = minVertexCovers2;
}
for (Vertex v : result) {
invitees.add(v.getId());
}
}
