//
// rooting of tree at edge e
node StaticSPQRTree::rootTreeAt(edge e)
{
m_rootEdge = e;
m_rootNode = m_skOf[e]->treeNode();
m_sk[m_rootNode]->m_referenceEdge = m_copyOf[e];
rootRec(m_rootNode,nullptr);
return m_rootNode;
}
node StaticSPQRTree::rootTreeAt(node v)
{
m_rootEdge = nullptr;
m_rootNode = v;
m_sk[m_rootNode]->m_referenceEdge = nullptr;
rootRec(m_rootNode,nullptr);
return m_rootNode;
}
void StaticSPQRTree::rootRec(node v, edge eFather)
{
edge e;
forall_adj_edges(e,v)
{
if (e == eFather) continue;
node w = e->target();
if (w == v) {
m_tree.reverseEdge(e);
swap(m_skEdgeSrc[e],m_skEdgeTgt[e]);
w = e->target();
}
m_sk[w]->m_referenceEdge = m_skEdgeTgt[e];
rootRec(w,e);
}
}
void StaticSPQRTree::rootRec(node v, edge eFather)
{
for(adjEntry adj : v->adjEntries) {
edge e = adj->theEdge();
if (e == eFather) continue;
node w = e->target();
if (w == v) {
m_tree.reverseEdge(e);
swap(m_skEdgeSrc[e],m_skEdgeTgt[e]);
w = e->target();
}
m_sk[w]->m_referenceEdge = m_skEdgeTgt[e];
rootRec(w,e);
}
}
