struct State {
  int c; //256=epsilon, 257=accept
  
  State * next;

  //used only when c is epsilon, but could be null
  State * alt;

  bool visited;

  State(int c, State * next=0, State * alt=0) {
    this->c=c;
    this->next=next;
    this->alt=alt;
    visited=false;
  }

  bool isAccept()const {
    return c==257;
  }
  
  bool isSplit()const {
    return c==256;
  }
};

struct NFA {
  State * in;
  State * out;

  NFA(State * in, State * out) {
    this->in=in;
    this->out=out;
  }
}; 

NFA sym(int c) {
  State * s=new State(c);
  return NFA(s, s);
}

NFA dot(NFA nfa1, NFA nfa2) {
  nfa1.out->next=nfa2.in;
  return NFA(nfa1.in, nfa2.out);
}

NFA bar(NFA nfa1, NFA nfa2) {
  State * s=new State(256, nfa1.in, nfa2.in);
  State * t=new State(256);
  nfa1.out->next=nfa2.out->next=t;
  return NFA(s, t);
}

NFA que(NFA nfa) {
  State * t=new State(256);
  State * s=new State(256, nfa.in, t);
  nfa.out->next=t;
  return NFA(s, t);
}

NFA star(NFA nfa) {
  State * s=new State(256, 0, nfa.in);
  nfa.out->next=s;
  return NFA(s, s);
}

NFA plus(NFA nfa) {
  State * s=new State(256, 0, nfa.in);
  nfa.out->next=s;
  return NFA(nfa.in, s);
}

NFA accept(NFA nfa) {
  State * s=new State(257);
  nfa.out->next=s;
  return NFA(nfa.in, s);
}

void freeNFA(State * s) {
  if (!s || s->visited)
    return;
  s->visited=true;
  freeNFA(s->next);
  freeNFA(s->alt);
  delete s;
}

void freeNFA(NFA nfa) {
  freeNFA(nfa.in);
}

#include<vector>

using std::vector;

void in2post(const char * s, char * t) {
  vector<char> v; //empty stack
  int count=0;
  while (*s!='\0') { 
    if (*s=='|') {
      while (!v.empty() && 
	     v[v.size()-1]!='(') {
	t[count]=v[v.size()-1];
	v.pop_back();
	count++;
      }
      v.push_back(*s);
    }
    else
      if (*s=='.') {
	while(!v.empty() && 
	      v[v.size()-1]!='|' && 
	      v[v.size()-1]!='(') {
	  t[count]=v[v.size()-1];
	  v.pop_back();
	  count++;
	}
	v.push_back(*s);
      }
      else
	if (*s=='*' ||
	    *s=='+' ||
	    *s=='?')
	  v.push_back(*s);
	else
	  if (*s=='(') 
	    v.push_back(*s);
	  else
	    if (*s==')') {
	      while (v[v.size()-1]!='(') {
		t[count]=v[v.size()-1];
		v.pop_back();
		count++;
	      }
	      v.pop_back();
	    }
	    else {
	      t[count]=*s;
	      count++;
	    }
    s++;
  }
  while (!v.empty()) {
    t[count]=v[v.size()-1];
    v.pop_back();
    count++;
  }
  t[count]='\0';
}