} // end function TableFillingAlg
/// <summary>
/// Table Filling Algorithm EQ Classes
/// </summary>
/// <returns>Returns all TF EQ Classes</returns>
public static uint[][] TableFillingAlgEqClasses(Finite.DFA D) {
var tf = TableFillingAlg(D);
var eqClasses = new List<uint[]>((int)D.StatesCount);
int?[] State2eqClass = new int?[D.StatesCount];
// iterate table and process false(/double) values
for (uint x = 0; x < tf.GetLength(0); x++) {
for (uint y = x + 1; y < tf.GetLength(1); y++) {
if (!tf[x, y]) {
if (State2eqClass[x].HasValue) {
eqClasses[State2eqClass[x].Value] = eqClasses[State2eqClass[x].Value].Append(y).ToArray();
State2eqClass[y] = State2eqClass[x];
} else {
eqClasses.Add(new uint[] { x, y });
State2eqClass[x] = eqClasses.Count - 1;
State2eqClass[y] = eqClasses.Count - 1;
}
} // end if
} // next y
} // next x
// add all none processed states
for (uint i = 0; i < D.StatesCount; i++)
if (!State2eqClass[i].HasValue)
eqClasses.Add(new uint[] { i });
eqClasses.Sort((first, second) => first[0].CompareTo(second[0]));
return eqClasses.ToArray();
} // end function TableFillingAlgEqClasses
public static bool[,] TableFillingAlg(Finite.DFA D) {
bool[,] t = new bool[D.StatesCount, D.StatesCount];
// first, mark all states which differ between accepted and not
for (uint x = 0; x < t.GetLength(0); x++)
for (uint y = 0; y < t.GetLength(0); y++)
if (D.IsAcceptedState(x) != D.IsAcceptedState(y))
t[x, y] = true;
bool found; // loop while found something new
do {
found = false;
// iterate full table, for each char
for (uint x = 0; x < t.GetLength(0); x++) {
for (uint y = x + 1; y < t.GetLength(1); y++) {
if (!t[x, y]) { // don't work already processed (PERF)
foreach (char c in D.Alphabet) {
uint xNext = D.GoChar(x, c)[0];
uint yNext = D.GoChar(y, c)[0];
// calculate based on previous iterations
// if next states for both x,y has been set to different
// set current pair to be different, and enable loop
if (t[xNext, yNext])
t[x, y] = t[y, x] = found = true;
} // next c
} // end if
} // next y
} // next x
} while (found);
return t;
} // end function TableFillingAlg
