@SuppressWarnings("unchecked")
private void formSplitComponent(
V u,
V v,
V current,
List<E> coveredEdges,
List<V> coveredVertices,
SplitComponent<V, E> component,
Graph<V, E> graph) {
if (coveredVertices.contains(current)) return;
coveredVertices.add(current);
component.addVertex(current);
for (E e : graph.allEdges(current)) {
if (coveredEdges.contains(e)) continue;
coveredEdges.add(e);
component.addEdge(e);
V other = e.getDestination() == current ? e.getOrigin() : e.getDestination();
if (other != u && other != v) {
formSplitComponent(u, v, other, coveredEdges, coveredVertices, component, graph);
} else component.addVertex(other);
}
}
@SuppressWarnings("unchecked")
public List<SplitComponent<V, E>> findAllSplitComponents(
Graph<V, E> graph, SplitPair<V, E> splitPair) {
List<E> coveredEdges = new ArrayList<E>();
List<SplitComponent<V, E>> ret = new ArrayList<SplitComponent<V, E>>();
V u = splitPair.getU();
V v = splitPair.getV();
// add edge
List<E> edges = graph.edgeesBetween(u, v);
for (E e : edges) { // TODO sta ako stvarno ima vise izmedju, da li ovako, ili ne moze...?
SplitComponent<V, E> component = new SplitComponent<>(splitPair, graph);
component.addVertex(v);
component.addVertex(u);
component.addEdge(e);
coveredEdges.add(e);
ret.add(component);
}
for (E e : graph.allEdges(u)) {
if (coveredEdges.contains(e)) continue;
SplitComponent<V, E> component = new SplitComponent<>(splitPair, graph);
coveredEdges.add(e);
component.addVertex(u);
component.addEdge(e);
V other = e.getDestination() == u ? e.getOrigin() : e.getDestination();
if (other == v) // just add split pair vertices and the edge{
continue;
else {
formSplitComponent(u, v, other, coveredEdges, new ArrayList<V>(), component, graph);
}
ret.add(component);
}
return ret;
}
/**
* A pair {u,v} of vertices is a split pair if it is an edge in the graph or if it is a separation
* pair (it increases the number of connected components) in the graph (graph is no longer
* connected if it is removed)
*
* @param graph
* @return
*/
public List<SplitPair<V, E>> findAllSplitPairs(Graph<V, E> graph) {
List<SplitPair<V, E>> ret = new ArrayList<SplitPair<V, E>>();
List<V> excluding = new ArrayList<V>();
List<V> vertices = graph.getVertices();
for (int i = 0; i < vertices.size(); i++)
for (int j = i + 1; j < vertices.size(); j++) {
V v1 = vertices.get(i);
V v2 = vertices.get(j);
if (graph.hasEdge(v1, v2)) ret.add(new SplitPair<V, E>(v1, v2));
else {
excluding.clear();
excluding.add(v1);
excluding.add(v2);
if (!graph.isConnected(excluding)) {
ret.add(new SplitPair<V, E>(v1, v2));
}
}
}
return ret;
}
/**
* A cut vertex is a vertex whose removal would disconnect the remaining graph
*
* @param graph
* @return
*/
public List<V> findAllCutVertices(Graph<V, E> graph) {
return graph.listCutVertices();
}