public static IEnumerable <Regexp> SynthesizeRegexp(HashSet <char> alphabet, Automaton <BDD> dfa, CharSetSolver s, StringBuilder sb, long timeout)
{
using (System.IO.StreamWriter file = new System.IO.StreamWriter(@"..\..\..\regexpenum.txt"))
{
solver = s;
numStates = dfa.StateCount;
alph = alphabet;
#region test variables
StringBuilder sb1 = new StringBuilder();
int lim = 0;
Stopwatch membershipTimer = new Stopwatch();
Stopwatch equivTimer = new Stopwatch();
timer = new Stopwatch();
timer.Start();
#endregion
#region TestSets for equiv
var mytests = DFAUtilities.MyHillTestGeneration(alphabet, dfa, solver);
var posMN = mytests.First;
var negMN = mytests.Second;
var tests = DFAUtilities.GetTestSets(dfa, alphabet, solver);
var positive = tests.First;
var negative = tests.Second;
foreach (var t in posMN)
{
positive.Remove(t);
}
foreach (var t in negMN)
{
negative.Remove(t);
}
#endregion
#region Sigma Star
bool fst = true;
foreach (var c in alph)
{
if (fst)
{
fst = false;
sigmaStar = new RELabel(c);
}
else
{
sigmaStar = new REUnion(sigmaStar, new RELabel(c));
}
}
sigmaPlus = new REPlus(sigmaStar);
sigmaStar = new REStar(sigmaStar);
#endregion
#region Accessories vars
maxWidthC = 0;
maxSigmaStarC = 0;
var isSubset = true;
HashSet <string> visited = new HashSet <string>();
HashSet <string> newReg = new HashSet <string>();
currUnionEls = new Dictionary <string, Automaton <BDD> >();
memoDfa = new Dictionary <string, Automaton <BDD> >();
List <Regexp> subsetReg = new List <Regexp>();
#endregion
for (maxWidth = 1; true; maxWidth++)
{
newReg = new HashSet <string>();
maxSigmaStar = 2;
foreach (var regexp in EnumerateRegexp())
{
#region run for at most timeout
if (timer.ElapsedMilliseconds > timeout)
{
sb.AppendLine("| Timeout");
timer.Stop();
yield break;
}
#endregion
var re = regexp.Normalize();
if (!(visited.Contains(re.ToString())))
{
visited.Add(re.ToString());
sb1 = new StringBuilder();
sb1.Append(re.ToString());
file.WriteLine(sb1);
lim++;
#region Membership test
membershipTimer.Start();
isSubset = CorrectOnNegSet(regexp, negMN);
membershipTimer.Stop();
#endregion
#region equivalence check
if (isSubset)
{
membershipTimer.Start();
if (CorrectOnNegSet(regexp, negative))
{
if (CorrectOnPosSet(regexp, posMN) && CorrectOnPosSet(regexp, positive))
{
membershipTimer.Stop();
equivTimer.Start();
var rDfa = getDfa(regexp);
memoDfa[regexp.ToString()] = rDfa;
if (rDfa.IsEquivalentWith(dfa, solver))
{
isSubset = false;
equivTimer.Stop();
timer.Stop();
sb.Append("| ");
regexp.ToString(sb);
sb.AppendLine("|");
sb.AppendLine(string.Format("| elapsed time: \t {0} ms", timer.ElapsedMilliseconds));
sb.AppendLine(string.Format("| equivalence cost:\t {0} ms", equivTimer.ElapsedMilliseconds));
sb.AppendLine(string.Format("| membership cost: \t {0} ms", membershipTimer.ElapsedMilliseconds));
sb.AppendLine(string.Format("| attempts: \t {0}", lim));
yield return(regexp);
}
else
{
Console.WriteLine("used dfa");
equivTimer.Stop();
}
}
else
{
membershipTimer.Stop();
}
}
else
{
membershipTimer.Stop();
isSubset = false;
}
}
#endregion
//#region Subsets
//if (isSubset)
//{
// foreach (var reg1 in subsetReg)
// {
// var union = (reg1.CompareTo(regexp) > 0) ? (new REUnion(reg1, regexp)) : (new REUnion(regexp, reg1));
// visited.Add(union.ToString());
// sb1 = new StringBuilder();
// sb1.Append(union + " From union");
// file.WriteLine(sb1);
// lim++;
// membershipTimer.Start();
// if (CorrectOnPosSet(union, posMN) && CorrectOnPosSet(union, positive))
// {
// membershipTimer.Stop();
// equivTimer.Start();
// var rDfa = getDfa(union);
// memoDfa[union.ToString()] = rDfa;
// if (rDfa.IsEquivalentWith(dfa, solver))
// {
// equivTimer.Stop();
// timer.Stop();
// sb.Append("| ");
// union.ToString(sb);
// sb.AppendLine("|");
// sb.AppendLine(string.Format("| elapsed time: \t {0} ms", timer.ElapsedMilliseconds));
// sb.AppendLine(string.Format("| equivalence cost:\t {0} ms", equivTimer.ElapsedMilliseconds));
// sb.AppendLine(string.Format("| membership cost: \t {0} ms", membershipTimer.ElapsedMilliseconds));
// sb.AppendLine(string.Format("| attempts: \t {0}", lim));
// yield return union;
// }
// else
// {
// Console.WriteLine("used dfa");
// equivTimer.Stop();
// }
// }
// else
// {
// membershipTimer.Stop();
// }
// }
// subsetReg.Add(regexp);
//}
//#endregion
}
}
visited = new HashSet <string>(visited.Union(newReg));
}
}
}
/// <summary>
/// Finds min edit distance script between DFAs if operation
/// takes less than timeout ms
/// </summary>
/// <param name="dfa1"></param>
/// <param name="dfa2"></param>
/// <param name="al"></param>
/// <param name="solver"></param>
/// <param name="timeout"></param>
/// <param name="sb"></param>
/// <returns></returns>
public static DFAEditScript GetDFAOptimalEdit( // copy
Automaton <BDD> dfa1, Automaton <BDD> dfa2,
HashSet <char> al, CharSetSolver solver, long timeout,
StringBuilder sb)
{
//Contract.Assert(dfa1.IsDeterministic);
//Contract.Assert(dfa2.IsDeterministic);
DFAEditScript editScript = new DFAEditScript();
#region Add states to dfa2 to make it at least as dfa1
BDD fullAlphabetCondition = BDDOf(al, solver);
//Normalize the DFA giving only names from 0 to |States|-1
var normDfaPair = DFAUtilities.normalizeDFA(dfa2);
var dfa2augmented = normDfaPair.First;
//solver.SaveAsDot(dfa2augmented, "aaaa");
var stateNamesMapping = normDfaPair.Second;
//Add states to make dfa2 have the |dfa2.States|>= |dfa1.States|
var newMoves = new List <Move <BDD> >(dfa2augmented.GetMoves());
for (int i = 1; i <= dfa1.StateCount - dfa2augmented.StateCount; i++)
{
int newStateName = dfa2augmented.MaxState + i;
//Pick the next available name to be added
stateNamesMapping[newStateName] = dfa2.MaxState + i;
//save the operation in the script
editScript.script.Insert(0, new DFAAddState(dfa2.MaxState + i));
newMoves.Add(new Move <BDD>(newStateName, newStateName, fullAlphabetCondition));
newStateName++;
}
//Create the new DFA with the added states
dfa2augmented = Automaton <BDD> .Create(dfa2augmented.InitialState, dfa2augmented.GetFinalStates().ToList(), newMoves);
#endregion
int maxScore = (dfa1.StateCount + dfa2augmented.StateCount) * (al.Count + 1);
int oldScirptSize = editScript.script.Count;
//Start with the internal script equals to null, at the end bestScript.Script will contain the best script
DFAEditScript bestScript = new DFAEditScript();
bestScript.script = null;
Stopwatch sw = new Stopwatch();
sw.Start();
// Iteratively check if there exists an edit of a given depth
for (int depth = 1; true; depth++)
{
var editList = new List <DFAEdit>();
if (GetDFAEditScriptTimeout(
dfa1, dfa2augmented, al, solver,
new List <long>(), editScript.script,
depth, timeout, sw, DFAUtilities.MyHillTestGeneration(al, dfa1, solver),
DFADensity.GetDFADensity(dfa1, al, solver),
editScript.GetCost(), bestScript, stateNamesMapping))
{
// if hits timeout break and return null
break;
}
if (bestScript.script != null)
{
bestScript.script.Reverse();
sw.Stop();
return(bestScript);
}
}
sw.Stop();
return(null);
}
