void TarjanHD::run()
{
_T.clear();
NodeNodeMap mapToOrgG(_orgG, lemon::INVALID);
for (NodeIt v(_orgG); v != lemon::INVALID; ++v)
{
mapToOrgG[v] = v;
}
ArcList arcs;
for (ArcIt a(_orgG); a != lemon::INVALID; ++a)
{
arcs.push_back(a);
}
// sort by weight
arcs.sort(Comparison(_orgW));
BoolArcMap arcFilter(_orgG, true);
BoolNodeMap nodeFilter(_orgG, true);
NodeNodeMap G2T(_orgG, lemon::INVALID);
SubDigraph subG(_orgG, nodeFilter, arcFilter);
_root = hd(_orgG, _orgW, subG, mapToOrgG, G2T, arcs, 0);
fixTree(_root);
}
void TwoThreeTree::remove(TNode *d) {
if (root == d) {
delete d;
root = NULL;
return;
}
fixTree(d, d->side);
}
void TwoThreeTree::fixTwoNode(TNode *d, int s) {
TNode *p = d->parent;
// get d's sibling.
TNode *dSib = (s == -1) ? p->middle : p->left;
delete d;
// base case when d's parent is root
if (p == root) {
root = dSib;
dSib->parent = NULL;
delete p;
return;
}
// connect d's sibling to middle to unify different cases
connect(dSib, p, 0);
p->left = NULL;
p->right = NULL;
// get p's parent, which is d's grandparent
TNode *g = p->parent;
TNode *pSib = NULL;
// get p's sibling
if (g->rlow == -1)
pSib = (p->side == -1) ? g->middle : g->left;
else
pSib = (p->side == 0) ? g->left : g->middle;
if (pSib->rlow != -1) {
// if p's sibling is a 3-node, call adoptchild
adoptChild(p, pSib);
fixLowVals(p);
} else {
// if p's sibling is a 2-node, call lose child
loseChild(p, pSib);
// recursively fix p
fixTree(p, p->side);
}
}
