graph_t *KCoreGraph::subgraph(IntStack *vset) {
assert(!vset->empty());
graph_t *g = graph_new(maxsize());
IntStack *nb;
int val,preval,val2,preval2;
val = vset->head();
preval = val-1;
while (val != preval) {
nb = neighbourhoods.at(val);
if (!nb->empty()) {
val2 = nb->head();
preval2 = val2-1;
while (val2 != preval2) {
if ((val > val2) && vset->contain(val2)) GRAPH_ADD_EDGE(g,val,val2);
preval2 = val2;
val2 = nb->next(preval2);
}
}
preval = val;
val = vset->next(preval);
}
return g;
};
