private Verticle PerformTransition(Verticle from, C chr)
{
var transition = aTransition;
if (chr == C.B)
{
transition = bTransition;
}
foreach (var(t, i) in from.State.Select((t, i) => (t, i)))
{
if (t && transition[i] is null)
{
return(null);
}
}
var res = new bool[N];
foreach (var(s, i) in from.State.Select((s, i) => (s, i)))
{
if (s)
{
res[transition[i].Value] = true;
}
}
return(new Verticle(res));
}
public C[] Sync()
{
var start = new Verticle(Enumerable.Range(0, N).Select(_ => true).ToArray());
Verticle fin = null;
var passed = new HashSet <Verticle> {
start
};
var pred = new Dictionary <Verticle, Tuple <Verticle, C> >();
var collection = new Queue <Verticle>();
collection.Enqueue(start);
while (fin is null && collection.Count != 0)
{
var v = collection.Dequeue();
foreach (var c in _letters)
{
var u = PerformTransition(v, c);
if (u is null || passed.Contains(u))
{
continue;
}
pred[u] = Tuple.Create(v, c);
if (u.Count == 1)
{
fin = u;
}
passed.Add(u);
collection.Enqueue(u);
}
}
if (fin is null)
{
return new C[] { }
}
;
var res = new List <C>();
while (!fin.Equals(start))
{
var(v, c) = pred[fin];
res.Add(c);
fin = v;
}
res.Reverse();
return(res.ToArray());
}
