TreeTemplate<Node>* BipartitionList::toTree() const throw (Exception)
{
BipartitionList* sortedBipL;
vector<int*> sortedBitBipL;
int* bip;
vector<Node*> vecNd, sonNd;
vector<bool> alive;
size_t lword, nbword, nbint, ii;
/* check, copy and prepare bipartition list */
if (!BipartitionList::areAllCompatible())
throw Exception("Trying to build a tree from incompatible bipartitions");
sortedBipL = dynamic_cast<BipartitionList*>(clone());
for (size_t i = 0; i < sortedBipL->getNumberOfBipartitions(); i++)
{
if (sortedBipL->getPartitionSize(i) > sortedBipL->getNumberOfElements() / 2)
sortedBipL->flip(i);
}
sortedBipL->sortByPartitionSize();
sortedBipL->removeRedundantBipartitions();
sortedBitBipL = sortedBipL->getBitBipartitionList();
for (size_t i = 0; i < sortedBipL->getNumberOfBipartitions(); i++)
{
alive.push_back(true);
}
vecNd.resize(sortedBipL->getNumberOfBipartitions() + 1);
lword = static_cast<size_t>(BipartitionTools::LWORD);
nbword = (elements_.size() + lword - 1) / lword;
nbint = nbword * lword / (CHAR_BIT * sizeof(int));
bip = new int[1]; bip[0] = 0;
/* main loop: create one node per bipartition */
for (size_t i = 0; i < sortedBipL->getNumberOfBipartitions(); i++)
{
if (sortedBipL->getPartitionSize(i) == 1)
{ // terminal
for (size_t j = 0; j < sortedBipL->getNumberOfElements(); j++)
{
if (BipartitionTools::testBit(sortedBitBipL[i], static_cast<int>(j)))
{
vecNd[i] = new Node(elements_[j]);
break;
}
}
}
else
{ // internal
sonNd.clear();
for (size_t j = 0; j < i; j++)
{
if (alive[j])
{
for (ii = 0; ii < nbint; ii++)
{
BipartitionTools::bitOr(bip, sortedBitBipL[j] + ii, sortedBitBipL[i] + ii, 1);
if (bip[0] != sortedBitBipL[i][ii])
break;
}
if (ii == nbint)
{
sonNd.push_back(vecNd[j]);
alive[j] = false;
}
}
}
vecNd[i] = new Node();
for (size_t k = 0; k < sonNd.size(); k++)
{
vecNd[i]->addSon(sonNd[k]);
}
}
}
/* create last node, which joins alive bipartitions = fatherless nodes */
Node* rootNd = new Node();
for (size_t i = 0; i < sortedBipL->getNumberOfBipartitions(); i++)
{
if (alive[i])
rootNd->addSon(vecNd[i]);
}
/* construct tree and return */
TreeTemplate<Node>* tr = new TreeTemplate<Node>(rootNd);
tr->resetNodesId();
delete sortedBipL;
return tr;
}
