public static void Determinize(Automaton a, List <State> initialset)
{
var points = a.GetStartPoints();
var comparer = new ListEqualityComparer <State>();
var sets = new Dictionary <List <State>, List <State> >(comparer);
var worklist = new LinkedList <List <State> >();
var newstate = new Dictionary <List <State>, State>(comparer);
sets.Add(initialset, initialset);
_ = worklist.AddLast(initialset);
a.Initial = new State();
newstate.Add(initialset, a.Initial);
while (worklist.Count > 0)
{
var s = worklist.RemoveAndReturnFirst();
_ = newstate.TryGetValue(s, out var r);
foreach (var q in s)
{
if (q.Accept)
{
r.Accept = true;
break;
}
}
for (var n = 0; n < points.Length; n++)
{
var set = new HashSet <State>();
foreach (var c in s)
{
foreach (var t in c.Transitions)
{
if (t.Min <= points[n] && points[n] <= t.Max)
{
_ = set.Add(t.To);
}
}
}
var p = set.ToList();
if (!sets.ContainsKey(p))
{
sets.Add(p, p);
_ = worklist.AddLast(p);
newstate.Add(p, new State());
}
_ = newstate.TryGetValue(p, out var q);
var min = points[n];
var max = n + 1 < points.Length ? (char)(points[n + 1] - 1) : char.MaxValue;
r.Transitions.Add(new Transition(min, max, q));
}
}
a.IsDeterministic = true;
a.RemoveDeadTransitions();
}
public static Automaton Complement(Automaton a)
{
a = a.CloneExpandedIfRequired();
a.Determinize();
a.Totalize();
foreach (var p in a.GetStates())
{
p.Accept = !p.Accept;
}
a.RemoveDeadTransitions();
return(a);
}
public static Automaton Intersection(Automaton a1, Automaton a2)
{
if (a1.IsSingleton)
{
return(a2.Run(a1.Singleton) ? a1.CloneIfRequired() : BasicAutomata.MakeEmpty());
}
if (a2.IsSingleton)
{
return(a1.Run(a2.Singleton) ? a2.CloneIfRequired() : BasicAutomata.MakeEmpty());
}
if (a1 == a2)
{
return(a1.CloneIfRequired());
}
var transitions1 = Automaton.GetSortedTransitions(a1.GetStates());
var transitions2 = Automaton.GetSortedTransitions(a2.GetStates());
var c = new Automaton();
var worklist = new LinkedList <StatePair>();
var newstates = new Dictionary <StatePair, StatePair>();
var p = new StatePair(c.Initial, a1.Initial, a2.Initial);
_ = worklist.AddLast(p);
newstates.Add(p, p);
while (worklist.Count > 0)
{
p = worklist.RemoveAndReturnFirst();
p.S.Accept = p.FirstState.Accept && p.SecondState.Accept;
var t1 = transitions1[p.FirstState.Number];
var t2 = transitions2[p.SecondState.Number];
for (int n1 = 0, b2 = 0; n1 < t1.Length; n1++)
{
while (b2 < t2.Length && t2[b2].Max < t1[n1].Min)
{
b2++;
}
for (var n2 = b2; n2 < t2.Length && t1[n1].Max >= t2[n2].Min; n2++)
{
if (t2[n2].Max >= t1[n1].Min)
{
var q = new StatePair(t1[n1].To, t2[n2].To);
_ = newstates.TryGetValue(q, out var r);
if (r == null)
{
q.S = new State();
_ = worklist.AddLast(q);
newstates.Add(q, q);
r = q;
}
var min = t1[n1].Min > t2[n2].Min ? t1[n1].Min : t2[n2].Min;
var max = t1[n1].Max < t2[n2].Max ? t1[n1].Max : t2[n2].Max;
p.S.Transitions.Add(new Transition(min, max, r.S));
}
}
}
}
c.IsDeterministic = a1.IsDeterministic && a2.IsDeterministic;
c.RemoveDeadTransitions();
c.CheckMinimizeAlways();
return(c);
}
