#include"regexp.h"
#include<vector>
using std::vector;

void __reachable(State * s, vector<State *>& v) {
  if (!s || s->visited)
    return;
  v.push_back(s);
  s->visited=true;
  if (s->isSplit()) {
    __reachable(s->next, v);
    __reachable(s->alt, v);
  }
}
    
vector<State *> reachable(const vector<State *>& list) {
  vector<State *> v;
  for (int i=0; i<list.size(); i++)
    if (list[i])
      __reachable(list[i], v); //fill vector
  for (int i=0; i<v.size(); i++) //clear visited
    v[i]->visited=false;
  return v;
}

bool runNFA(NFA nfa, char * exp) {
  int pos=0;
  vector<State *> list1;
  vector<State *> list2; 
  list1.push_back(nfa.in);
  list1=reachable(list1);
  while (*exp!='\0') {
    for (int i=0; i<list1.size(); i++)
      if (list1[i]->c==*exp || list1[i]->c=='!') { //! is wild card 
	list2.push_back(list1[i]->next);
	if (list1[i]->alt)
	  list2.push_back(list1[i]->alt);
      }
    list1=reachable(list2); //new list
    //for (int i=0; i<list1.size(); i++) 
    //  if (list1[i]->isAccept())
    //    pos is the end of a match
    list2=vector<State *>(); //empty
    exp++;
    pos++;
  }
  for (int i=0; i<list1.size(); i++) 
    if (list1[i]->isAccept())
      return true;
  return false;
}