double Graph::MSTAlgo() {
DisjointSet<Vertex>* A = new DisjointSet<Vertex>(n);
double totalweight = 0;
for(int i = 0; i < n; ++i){
A->MakeSet(i, AdjacencyList[i]->getElem());
}
sortEdge();
for(int i = 0; i < EdgeList.size(); ++i){
if(A->FindSet(EdgeList[i]->vertex_i)->getKey() != A->FindSet(EdgeList[i]->vertex_j)->getKey()){
A->Union(*(A->FindSet(EdgeList[i]->vertex_i)), *(A->FindSet(EdgeList[i]->vertex_j)));
totalweight += EdgeList[i]->weight;
MST.push_back(EdgeList[i]);
}
}
return totalweight;
}
int main(int argc, char *argv[]) {
DisjointSet ds;
for (int set_number=0; set_number<DSET_SIZE; ++set_number) {
ds.MakeSet(set_number);
}
srand(time(NULL));
int unions = 0;
int attempts = 0;
while (ds.size() > 1) {
// generate random couples and do Union operations, up to when there is
// only a single set left.
int x = rand() % DSET_SIZE;
int y = rand() % DSET_SIZE;
if (ds.Union(x,y)) {
unions += 1;
} else {
attempts += 1;
}
//std::cout << ds.toDot() << std::endl;
}
std::cerr << "unions=" << unions << ", attempts=" << attempts << std::endl;
std::cout << ds.toDot() << std::endl;
return 0;
}