public DFSM(FSM <T> fsm) : this()
{
List <BuildSet> marked = new List <BuildSet>();
marked.Add(new BuildSet(new int[] { 0 }));
for (int j = 0; j < marked.Count; j++)
{
foreach (T s in fsm.Symbols)
{
List <int> acumulator = new List <int>();
foreach (int i in marked[j].Items)
{
acumulator.AddRange(fsm.StatesFrom(i, s));
}
if (acumulator.Count > 0)
{
BuildSet set = new BuildSet(acumulator);
if (!marked.Contains(set))
{
marked.Add(set);
}
int k = marked.IndexOf(set);
if (!this._transitions.ContainsKey(j))
{
this._transitions[j] = new Dictionary <T, List <int> >();
}
if (!this._transitions[j].ContainsKey(s))
{
this._transitions[j][s] = new List <int>();
}
if (!this._transitions[j][s].Contains(k))
{
this._transitions[j][s].Add(k);
}
foreach (int fs in set.Items)
{
if (fsm.AcceptingStates.ContainsKey(fs))
{
if (!this.AcceptingStates.ContainsKey(k))
{
this.AcceptingStates[k] = new List <string>();
}
this.AcceptingStates[k].AddRange(fsm.AcceptingStates[fs].Except(this.AcceptingStates[k]));
}
}
}
}
}
}
public DFSM <T> Minimize()
{
DFSM <T> result = new DFSM <T>();
//make clone
result._transitions = new Dictionary <int, Dictionary <T, List <int> > >();
foreach (int i in this._transitions.Keys)
{
result._transitions[i] = new Dictionary <T, List <int> >();
foreach (T s in this._transitions[i].Keys)
{
result._transitions[i][s] = new List <int>(this._transitions[i][s]);
}
}
foreach (KeyValuePair <int, List <string> > kv in this.AcceptingStates)
{
result.AcceptingStates[kv.Key] = new List <string>(kv.Value);
}
//remove unreachable and looped states
result.Trim();
List <int> states = result.States;
List <int> acc = result.AcceptingStates.Keys.ToList();
List <int> nonacc = result.States.Except(acc).ToList();
List <T> symbols = result.Symbols;
List <BuildSet> distinctsets = new List <BuildSet>();
List <BuildSet> sets = new List <BuildSet>();
Dictionary <BuildSet, List <BuildSet> > deltasets = new Dictionary <BuildSet, List <BuildSet> >();
//populate all sets
for (int i = 0; i < states.Count; i++)
{
for (int j = i + 1; j < states.Count; j++)
{
BuildSet newset = new BuildSet(new int[] { states[i], states[j] });
sets.Add(newset);
if ((acc.Contains(states[i]) && nonacc.Contains(states[j])) || (acc.Contains(states[j]) && nonacc.Contains(states[i])))
{
distinctsets.Add(newset);
}
else
{
if (!deltasets.ContainsKey(newset))
{
deltasets[newset] = new List <BuildSet>();
}
foreach (T s in symbols)
{
foreach (int x in result.StatesFrom(states[i], s))
{
foreach (int y in result.StatesFrom(states[j], s))
{
if (x != y)
{
deltasets[newset].Add(new BuildSet(new int[] { x, y }));
}
}
}
}
deltasets[newset] = deltasets[newset].Distinct().ToList();
}
}
}
//mark all distinct states
int distcounter = 0;
while (distinctsets.Count != distcounter)
{
distcounter = distinctsets.Count;
foreach (BuildSet bs in deltasets.Keys)
{
if (deltasets[bs].Intersect(distinctsets).Any())
{
distinctsets.Add(bs);
}
if (deltasets[bs].Count == 0)
{
distinctsets.Add(bs);
}
}
distinctsets = distinctsets.Distinct().ToList();
foreach (BuildSet bs in distinctsets)
{
deltasets.Remove(bs);
}
}
//join mergeble sets
List <BuildSet> identicsets = sets.Except(distinctsets).ToList();
for (int i = 0; i < identicsets.Count; i++)
{
for (int j = i + 1; j < identicsets.Count; j++)
{
if (identicsets[i].Items.Intersect(identicsets[j].Items).Any())
{
List <int> newset = identicsets[i].Items.Union(identicsets[j].Items).ToList();
identicsets.RemoveAt(j);
identicsets.RemoveAt(i);
identicsets.Insert(i, new BuildSet(newset));
j = i;
}
}
}
foreach (BuildSet b in identicsets)
{
List <int> items = new List <int>(b.Items);
while (items.Count > 1)
{
result.RenumberState(items[1], items[0]);
items.RemoveAt(1);
}
}
return(result);
}
