unique_ptr<NFA> RepeatExp::buildNFA()
{
assert(childCount() == 1);
NFA* nfa = new NFA();
nfa->allocPoint();
nfa->addEdge(0, epsilon, 1);
unique_ptr<NFA> cnfa = firstChild()->buildNFA();
nfa->merge(*cnfa, std::make_pair(nfa->endPoint(), 0));
nfa->addEdge(nfa->endPoint(), epsilon, 1);
nfa->addEdge(0, epsilon, nfa->endPoint());
return unique_ptr<NFA>(nfa);
}
unique_ptr<NFA> OrExp::buildNFA()
{
NFA* nfa = new NFA();
std::vector<int> v;
for (auto& child : m_childExps)
{
unique_ptr<NFA> cnfa = child->buildNFA();
int ne = nfa->merge(*cnfa, std::make_pair(0, 0));
v.push_back(ne);
}
int end = nfa->allocPoint();
for (int ne : v)
{
nfa->addEdge(ne, epsilon, end);
}
return unique_ptr<NFA>(nfa);
}
unique_ptr<NFA> CharExp::buildNFA()
{
NFA* nfa = new NFA();
nfa->addEdge(0, getChar());
return unique_ptr<NFA>(nfa);
}
