public void TestRealDPDAToNormalForm() { var dpda = new PDA <char, char>(new AcceptanceCondition.EmptyStack(), true, 'Z', false, "ZYX", 'A'); dpda.AddState(1, false); dpda.AddTransition().From(0).To(0).Read('a').Pop('Z').Push("XZ"); dpda.AddTransition().From(0).To(0).Read('a').Pop('X').Push("XX"); dpda.AddTransition().From(0).To(0).Read('a').Pop('Y').Push("XY"); dpda.AddTransition().From(0).To(0).Read('b').Pop('Z').Push("YZ"); dpda.AddTransition().From(0).To(0).Read('b').Pop('X').Push("YX"); dpda.AddTransition().From(0).To(0).Read('b').Pop('Y').Push("YY"); dpda.AddTransition().From(0).To(1).Read('x').Pop('Z').Push("Z"); dpda.AddTransition().From(0).To(1).Read('x').Pop('X').Push("X"); dpda.AddTransition().From(0).To(1).Read('x').Pop('Y').Push("Y"); dpda.AddTransition().From(1).To(1).Read('a').Pop('X').Push(); dpda.AddTransition().From(1).To(1).Read('b').Pop('Y').Push(); dpda.AddTransition().From(1).To(1).Read().Pop('Z').Push(); var dpdaInNormalForm = DPDAToNormalFormConverter <char, char> .ToNormalForm(dpda); dpda.CreateRunner(); dpdaInNormalForm.CreateRunner(); var equalityResult = new PDAEqualityResult <char, StackSymbolSequence <char> >(dpda, dpdaInNormalForm, "abx", 10, 600000, 3000); Assert.IsTrue(equalityResult.AreEqual); }
public void MergeDPDAsWithEmptyStackTest() { var dpda1 = new PDA <char, char>(new AcceptanceCondition.EmptyStack(), true, 'A', false, "ABC", 'Z'); dpda1.AddState(1, false); dpda1.AddState(2, false); dpda1.AddState(3, false); dpda1.AddState(4, false); dpda1.AddState(5, false); dpda1.AddState(6, false); dpda1.AddState(7, false); dpda1.AddTransition().From(0).To(1).Read().Pop('A').Push("AAA"); dpda1.AddTransition().From(1).To(2).Read('a').Pop('A').Push(); dpda1.AddTransition().From(2).To(3).Read('a').Pop('A').Push(); dpda1.AddTransition().From(3).To(4).Read().Pop('A').Push("BBCC"); dpda1.AddTransition().From(4).To(4).Read('b').Pop('B').Push(); dpda1.AddTransition().From(4).To(4).Read('c').Pop('C').Push(); dpda1.AddTransition().From(1).To(5).Read().Pop('B').Push(); dpda1.AddTransition().From(2).To(6).Read().Pop('B').Push("B"); dpda1.AddTransition().From(6).To(7).Read().Pop('B').Push("B"); dpda1.AddTransition().From(7).To(6).Read().Pop('B').Push("B"); var dpda2 = new PDA <char, char>(new AcceptanceCondition.EmptyStack(), true, 'A', false, "ABC", 'Z'); dpda2.AddState(1, false); dpda2.AddState(2, false); dpda2.AddState(3, false); dpda2.AddState(4, false); dpda2.AddTransition().From(0).To(1).Read().Pop('A').Push("AAA"); dpda2.AddTransition().From(1).To(2).Read('a').Pop('A').Push(); dpda2.AddTransition().From(2).To(3).Read('a').Pop('A').Push(); dpda2.AddTransition().From(3).To(4).Read().Pop('A').Push("BBCC"); dpda2.AddTransition().From(4).To(4).Read('b').Pop('B').Push(); dpda2.AddTransition().From(4).To(4).Read('c').Pop('C').Push(); var mergedDPDAForSimulationOf1 = PDATransformer <char, char> .MergeDPDAsWithEmptyStack(dpda1, dpda2, 'X', 'Y'); dpda1.CreateRunner(); mergedDPDAForSimulationOf1.CreateRunner(); var equalityResult1 = new PDAEqualityResult <char, char>(dpda1, mergedDPDAForSimulationOf1, "abc", 10, 400000, 3000); Assert.IsTrue(equalityResult1.AreEqual); var mergedDPDAForSimulationOf2 = PDATransformer <char, char> .MergeDPDAsWithEmptyStack(dpda2, dpda1, 'X', 'Y'); dpda2.CreateRunner(); mergedDPDAForSimulationOf2.CreateRunner(); var equalityResult2 = new PDAEqualityResult <char, char>(dpda2, mergedDPDAForSimulationOf2, "abc", 10, 400000, 3000); Assert.IsTrue(equalityResult2.AreEqual); }
public void TestMaximumNumberOfWords() { var pda1 = new PDA <char, char>(new AcceptanceCondition.EmptyStack(), false, 'Z', false, "ZXY"); pda1.AddState(1, false); pda1.AddTransition().From(0).To(0).Read('a').Pop('Z').Push("XZ"); pda1.AddTransition().From(0).To(0).Read('a').Pop('X').Push("XX"); pda1.AddTransition().From(0).To(0).Read('a').Pop('Y').Push("XY"); pda1.AddTransition().From(0).To(0).Read('b').Pop('Z').Push("YZ"); pda1.AddTransition().From(0).To(0).Read('b').Pop('X').Push("YX"); pda1.AddTransition().From(0).To(0).Read('b').Pop('Y').Push("YY"); pda1.AddTransition().From(0).To(1).Read().Pop('Z').Push("Z"); pda1.AddTransition().From(0).To(1).Read().Pop('X').Push("X"); pda1.AddTransition().From(0).To(1).Read().Pop('Y').Push("Y"); pda1.AddTransition().From(1).To(1).Read('c').Pop('X').Push(); pda1.AddTransition().From(1).To(1).Read('d').Pop('Y').Push(); pda1.AddTransition().From(1).To(1).Read().Pop('Z').Push(); var pda2 = new PDA <char, char>(new AcceptanceCondition.EmptyStack(), false, 'Z', false, "ZXY"); pda2.AddState(1, false); pda2.AddTransition().From(0).To(0).Read('a').Pop('Z').Push("XZ"); pda2.AddTransition().From(0).To(0).Read('a').Pop('X').Push("XX"); pda2.AddTransition().From(0).To(0).Read('a').Pop('Y').Push("XY"); pda2.AddTransition().From(0).To(0).Read('b').Pop('Z').Push("YZ"); pda2.AddTransition().From(0).To(0).Read('b').Pop('X').Push("YX"); pda2.AddTransition().From(0).To(0).Read('b').Pop('Y').Push("YY"); pda2.AddTransition().From(0).To(1).Read().Pop('Z').Push("Z"); pda2.AddTransition().From(0).To(1).Read().Pop('X').Push("X"); pda2.AddTransition().From(0).To(1).Read().Pop('Y').Push("Y"); pda2.AddTransition().From(1).To(1).Read('c').Pop('X').Push(); pda2.AddTransition().From(1).To(1).Read('d').Pop('Y').Push(); pda2.AddTransition().From(1).To(1).Read('a').Pop('Z').Push(); pda1.CreateRunner(); pda2.CreateRunner(); var watch = new Stopwatch(); watch.Start(); var res = new PDAEqualityResult <char, char>(pda1, pda2, "abcd", 10, 400000, 60000); watch.Stop(); Console.WriteLine(watch.ElapsedMilliseconds); Assert.IsFalse(res.AreEqual); }
public void ToSDAInNormalFormTest() { var dpda = new PDA <char, char>(new AcceptanceCondition.EmptyStack(), true, 'Z', false, "ZA"); dpda.AddState(1, false); dpda.HasNormalForm(); dpda.AddTransition().From(0).To(0).Read('a').Pop('Z').Push("AZ"); dpda.AddTransition().From(0).To(0).Read('a').Pop('A').Push("AA"); dpda.AddTransition().From(0).To(1).Read('b').Pop('A').Push("A"); dpda.AddTransition().From(1).To(1).Read('c').Pop('A').Push(); dpda.AddTransition().From(1).To(1).Read().Pop('Z').Push(); var symbols = new Dictionary <string, TripleStackSymbol <char> >() { { "0A1", new TripleStackSymbol <char>(0, 'A', 1) }, { "0Z1", new TripleStackSymbol <char>(0, 'Z', 1) }, { "1A1", new TripleStackSymbol <char>(1, 'A', 1) } }; var exp = new SDA <char, TripleStackSymbol <char> >(symbols.Values); exp.AddTransition('a', symbols["0Z1"], new TripleStackSymbol <char>[] { symbols["0A1"] }); exp.AddTransition('a', symbols["0A1"], new TripleStackSymbol <char>[] { symbols["0A1"], symbols["1A1"] }); exp.AddTransition('b', symbols["0A1"], new TripleStackSymbol <char>[] { symbols["1A1"] }); exp.AddTransition('c', symbols["1A1"]); var act = DPDAInNormalFormToSDAConverter <char, char> .ToSDAInNormalForm(dpda).sda; Assert.IsTrue(exp.Equals(act)); var actPDA = act.ToPDA(symbols["0Z1"]); actPDA.CreateRunner(); dpda.CreateRunner(); var equalityResult = new PDAEqualityResult <char, TripleStackSymbol <char> >(dpda, actPDA, "abc", 7, 300000, 3000); Assert.IsTrue(equalityResult.AreEqual); var actDeterminisedSDA = DeterminisedSDA <char, TripleStackSymbol <char> > .FromSDAInNormalForm(act); actDeterminisedSDA.CalculateShortestWordsOfStackSymbols(); Assert.IsTrue(actDeterminisedSDA.ShortestWordsOfStackSymbols[symbols["1A1"]].SequenceEqual("c")); Assert.IsTrue(actDeterminisedSDA.ShortestWordsOfStackSymbols[symbols["0A1"]].SequenceEqual("bc")); Assert.IsTrue(actDeterminisedSDA.ShortestWordsOfStackSymbols[symbols["0Z1"]].SequenceEqual("abc")); }
public void TestMethod() { var pdaMirrored = new PDA <char, char>(new AcceptanceCondition.EmptyStack(), false, 'Z', false, "ZAB"); pdaMirrored.AddState(1, false); pdaMirrored.AddTransition().From(0).To(0).Read('a').Pop('Z').Push("AZ"); pdaMirrored.AddTransition().From(0).To(0).Read('a').Pop('A').Push("AA"); pdaMirrored.AddTransition().From(0).To(0).Read('a').Pop('B').Push("AB"); pdaMirrored.AddTransition().From(0).To(0).Read('b').Pop('Z').Push("BZ"); pdaMirrored.AddTransition().From(0).To(0).Read('b').Pop('A').Push("BA"); pdaMirrored.AddTransition().From(0).To(0).Read('b').Pop('B').Push("BB"); pdaMirrored.AddTransition().From(0).To(1).Read().Pop('Z').Push("Z"); pdaMirrored.AddTransition().From(0).To(1).Read().Pop('A').Push("A"); pdaMirrored.AddTransition().From(0).To(1).Read().Pop('B').Push("B"); pdaMirrored.AddTransition().From(0).To(1).Read('a').Pop('Z').Push("Z"); pdaMirrored.AddTransition().From(0).To(1).Read('a').Pop('A').Push("A"); pdaMirrored.AddTransition().From(0).To(1).Read('a').Pop('B').Push("B"); pdaMirrored.AddTransition().From(0).To(1).Read('b').Pop('Z').Push("Z"); pdaMirrored.AddTransition().From(0).To(1).Read('b').Pop('A').Push("A"); pdaMirrored.AddTransition().From(0).To(1).Read('b').Pop('B').Push("B"); pdaMirrored.AddTransition().From(1).To(1).Read('a').Pop('A').Push(); pdaMirrored.AddTransition().From(1).To(1).Read('b').Pop('B').Push(); pdaMirrored.AddTransition().From(1).To(1).Read().Pop('Z').Push(); pdaMirrored.CreateRunner(); var pdaMirroredEven = new PDA <char, char>(new AcceptanceCondition.EmptyStack(), false, 'Z', false, "ZAB"); pdaMirroredEven.AddState(1, false); pdaMirroredEven.AddTransition().From(0).To(0).Read('a').Pop('Z').Push("AZ"); pdaMirroredEven.AddTransition().From(0).To(0).Read('a').Pop('A').Push("AA"); pdaMirroredEven.AddTransition().From(0).To(0).Read('a').Pop('B').Push("AB"); pdaMirroredEven.AddTransition().From(0).To(0).Read('b').Pop('Z').Push("BZ"); pdaMirroredEven.AddTransition().From(0).To(0).Read('b').Pop('A').Push("BA"); pdaMirroredEven.AddTransition().From(0).To(0).Read('b').Pop('B').Push("BB"); pdaMirroredEven.AddTransition().From(0).To(1).Read().Pop('Z').Push("Z"); pdaMirroredEven.AddTransition().From(0).To(1).Read().Pop('A').Push("A"); pdaMirroredEven.AddTransition().From(0).To(1).Read().Pop('B').Push("B"); pdaMirroredEven.AddTransition().From(0).To(1).Read('a').Pop('Z').Push("Z"); pdaMirroredEven.AddTransition().From(0).To(1).Read('a').Pop('A').Push("A"); pdaMirroredEven.AddTransition().From(0).To(1).Read('a').Pop('B').Push("B"); pdaMirroredEven.AddTransition().From(0).To(1).Read('b').Pop('Z').Push("Z"); pdaMirroredEven.AddTransition().From(0).To(1).Read('b').Pop('A').Push("A"); pdaMirroredEven.AddTransition().From(1).To(1).Read('a').Pop('A').Push(); pdaMirroredEven.AddTransition().From(1).To(1).Read('b').Pop('B').Push(); pdaMirroredEven.AddTransition().From(1).To(1).Read().Pop('Z').Push(); pdaMirroredEven.AddTransition().From(1).To(1).Read('a').Pop('Z').Push(); pdaMirroredEven.CreateRunner(); var s = new Stopwatch(); var results = new Dictionary <int, List <Tuple <bool, TimeSpan> > >(); for (int i = 1; i <= 15; i++) { results[i] = new List <Tuple <bool, TimeSpan> >(); } for (int j = 0; j < 1; j++) //TODO: count until 10 for a good average { for (int i = 1; i <= 15; i++) { s.Restart(); var eq = new PDAEqualityResult <char, char>(pdaMirrored, pdaMirroredEven, "ab", i, 65535, 20000); s.Stop(); results[i].Add(new Tuple <bool, TimeSpan>(eq.AreEqual, s.Elapsed)); } } foreach (var t in results) { var equal = t.Value.All(v => v.Item1); var time = t.Value.Average(v => v.Item2.TotalMilliseconds); Console.WriteLine(string.Format("Maximum word length: {0}; Equal: {1}; Time: {2}", t.Key, equal, time)); } }
public void TestDPDAToNormalForm() { var dpda = new PDA <char, char>(new AcceptanceCondition.EmptyStack(), true, 'A', false, "ABC", 'Z'); dpda.AddState(1, false); dpda.AddState(2, false); dpda.AddState(3, false); dpda.AddState(4, false); dpda.AddState(5, false); dpda.AddState(6, false); dpda.AddState(7, false); dpda.AddTransition().From(0).To(1).Read().Pop('A').Push("AAA"); dpda.AddTransition().From(1).To(2).Read('a').Pop('A').Push(); dpda.AddTransition().From(2).To(3).Read('a').Pop('A').Push(); dpda.AddTransition().From(3).To(4).Read().Pop('A').Push("BBCC"); dpda.AddTransition().From(4).To(4).Read('b').Pop('B').Push(); dpda.AddTransition().From(4).To(4).Read('c').Pop('C').Push(); dpda.AddTransition().From(1).To(5).Read().Pop('B').Push(); dpda.AddTransition().From(2).To(6).Read().Pop('B').Push("B"); dpda.AddTransition().From(6).To(7).Read().Pop('B').Push("B"); dpda.AddTransition().From(7).To(6).Read().Pop('B').Push("B"); var allStackSymbols = new List <StackSymbolSequence <char> >() { new StackSymbolSequence <char>("A"), new StackSymbolSequence <char>("B"), new StackSymbolSequence <char>("C"), new StackSymbolSequence <char>("AA"), new StackSymbolSequence <char>("AAA"), new StackSymbolSequence <char>("BBCC"), new StackSymbolSequence <char>("BCC"), new StackSymbolSequence <char>("CC"), }; var exp = new PDA <char, StackSymbolSequence <char> >(new AcceptanceCondition.EmptyStack(), true, new StackSymbolSequence <char>('A'), false, allStackSymbols); exp.AddState(1, false); exp.AddState(2, false); exp.AddState(3, false); exp.AddState(4, false); exp.AddState(5, false); exp.AddState(6, false); exp.AddState(7, false); exp.AddTransition().From(0).To(2).Read('a').Pop(new StackSymbolSequence <char>("A")).Push(new StackSymbolSequence <char>[] { new StackSymbolSequence <char>("AA") }); exp.AddTransition().From(0).To(2).Read('a').Pop(new StackSymbolSequence <char>("AA")).Push(new StackSymbolSequence <char>[] { new StackSymbolSequence <char>("AA"), new StackSymbolSequence <char>("A") }); exp.AddTransition().From(0).To(2).Read('a').Pop(new StackSymbolSequence <char>("AAA")).Push(new StackSymbolSequence <char>[] { new StackSymbolSequence <char>("AA"), new StackSymbolSequence <char>("AA") }); exp.AddTransition().From(1).To(5).Read().Pop(new StackSymbolSequence <char>("B")).Push(); exp.AddTransition().From(1).To(2).Read('a').Pop(new StackSymbolSequence <char>("A")).Push(); exp.AddTransition().From(1).To(2).Read('a').Pop(new StackSymbolSequence <char>("AA")).Push(new StackSymbolSequence <char>[] { new StackSymbolSequence <char>("A") }); exp.AddTransition().From(1).To(2).Read('a').Pop(new StackSymbolSequence <char>("AAA")).Push(new StackSymbolSequence <char>[] { new StackSymbolSequence <char>("AA") }); exp.AddTransition().From(2).To(3).Read('a').Pop(new StackSymbolSequence <char>("A")).Push(); exp.AddTransition().From(2).To(3).Read('a').Pop(new StackSymbolSequence <char>("AA")).Push(new StackSymbolSequence <char>[] { new StackSymbolSequence <char>("A") }); exp.AddTransition().From(2).To(3).Read('a').Pop(new StackSymbolSequence <char>("AAA")).Push(new StackSymbolSequence <char>[] { new StackSymbolSequence <char>("AA") }); exp.AddTransition().From(3).To(4).Read('b').Pop(new StackSymbolSequence <char>("A")).Push(new StackSymbolSequence <char>[] { new StackSymbolSequence <char>("BCC") }); exp.AddTransition().From(3).To(4).Read('b').Pop(new StackSymbolSequence <char>("AA")).Push(new StackSymbolSequence <char>[] { new StackSymbolSequence <char>("BCC"), new StackSymbolSequence <char>("A") }); exp.AddTransition().From(3).To(4).Read('b').Pop(new StackSymbolSequence <char>("AAA")).Push(new StackSymbolSequence <char>[] { new StackSymbolSequence <char>("BCC"), new StackSymbolSequence <char>("AA") }); exp.AddTransition().From(4).To(4).Read('b').Pop(new StackSymbolSequence <char>("B")).Push(); exp.AddTransition().From(4).To(4).Read('b').Pop(new StackSymbolSequence <char>("BCC")).Push(new StackSymbolSequence <char>[] { new StackSymbolSequence <char>("CC") }); exp.AddTransition().From(4).To(4).Read('b').Pop(new StackSymbolSequence <char>("BBCC")).Push(new StackSymbolSequence <char>[] { new StackSymbolSequence <char>("BCC") }); exp.AddTransition().From(4).To(4).Read('c').Pop(new StackSymbolSequence <char>("C")).Push(); exp.AddTransition().From(4).To(4).Read('c').Pop(new StackSymbolSequence <char>("CC")).Push(new StackSymbolSequence <char>[] { new StackSymbolSequence <char>("C") }); var act = DPDAToNormalFormConverter <char, char> .ToNormalForm(dpda); Assert.IsTrue(exp.Equals(act)); dpda.CreateRunner(); exp.CreateRunner(); act.CreateRunner(); var equalityResult1 = new PDAEqualityResult <StackSymbolSequence <char>, StackSymbolSequence <char> >(exp, act, "abc", 7, 300000, 3000); Assert.IsTrue(equalityResult1.AreEqual); var equalityResult2 = new PDAEqualityResult <char, StackSymbolSequence <char> >(dpda, act, "abc", 10, 600000, 3000); Assert.IsTrue(equalityResult2.AreEqual); //this is actually unnecessary Assert.IsTrue(act.AcceptsWord("aabbcc").Accepts()); Assert.IsTrue(!act.AcceptsWord("aabbc").Accepts()); Assert.IsTrue(!act.AcceptsWord("aabcc").Accepts()); Assert.IsTrue(!act.AcceptsWord("abbcc").Accepts()); Assert.IsTrue(!act.AcceptsWord("").Accepts()); }
private static XElement TryToGradeConstructionProblem(XElement xmlPdaCorrect, XElement xmlPdaAttempt, XElement xmlGiveStackAlphabet, XElement xmlMaxGrade, CancellationToken token) { var pdaCorrect = PDA <char, char> .FromXml(xmlPdaCorrect); pdaCorrect.CreateRunner(token); var pdaAttempt = PDA <char, char> .FromXml(xmlPdaAttempt); pdaAttempt.CreateRunner(token); var giveStackAlphabet = bool.Parse(xmlGiveStackAlphabet.Value); var maxGrade = int.Parse(xmlMaxGrade.Value); var alphabet = PDAXmlParser.ParseAlphabetFromXmlPDA(xmlPdaCorrect); Assertion.Assert(Enumerable.SequenceEqual(alphabet, PDAXmlParser.ParseAlphabetFromXmlPDA(xmlPdaAttempt)), "the alphabets of the given PDAs are not the same"); var stackAlphabetCorrect = PDAXmlParser.ParseStackAlphabetFromXmlPDA(xmlPdaCorrect); var stackAlphabetAttempt = PDAXmlParser.ParseStackAlphabetFromXmlPDA(xmlPdaAttempt); Assertion.Assert(!giveStackAlphabet || Enumerable.SequenceEqual(stackAlphabetCorrect, stackAlphabetAttempt), "if the stack-alphabet is given for the solver, the attempt pda has to have the same stack-alphabet"); int statesDiff = pdaAttempt.States.Count - pdaCorrect.States.Count; int stackDiff = stackAlphabetAttempt.Count - stackAlphabetCorrect.Count; PDAEqualityResult <char, char> pdaEqualityResult; pdaEqualityResult = new PDAEqualityResult <char, char>(pdaCorrect, pdaAttempt, alphabet, maximumWordLengthTested, maximumNumberOfWords, maximumMilliSeconds); if (pdaEqualityResult.PdaCorrectIsinconsistent) { return(Grader.CreateXmlFeedback(maxGrade, new List <string>() { "Oops! Seems like your tutor created an inconsistent pda...therefore, you get the full grade ;)" })); } int joinSize = pdaEqualityResult.NumberOfWordsAcceptedByAtLeastOne; double proportion = joinSize == 0 ? 1 : (double)pdaEqualityResult.NumberOfWordsAcceptedByBoth / joinSize; int grade = (int)(maxGrade * proportion); var feedback = new List <string>(); if (!pdaEqualityResult.AreEqual) { if (pdaEqualityResult.WordsInPdaCorrectButNotInPdaAttempt.Count() == 0 && pdaEqualityResult.WordsInPdaAttemptButNotInPdaCorrect.Count() > 0) { feedback.Add(string.Format(HintSuperset)); } else if (pdaEqualityResult.WordsInPdaAttemptButNotInPdaCorrect.Count() == 0 && pdaEqualityResult.WordsInPdaCorrectButNotInPdaAttempt.Count() > 0) { feedback.Add(string.Format(HintSubset)); } if (pdaEqualityResult.WordsInPdaCorrectButNotInPdaAttempt.Count() > 0) { feedback.Add(string.Format(ErrorWordFalselyExcluded, FindWordWithMinimumLength(pdaEqualityResult.WordsInPdaCorrectButNotInPdaAttempt))); } if (pdaEqualityResult.WordsInPdaAttemptButNotInPdaCorrect.Count() > 0) { feedback.Add(string.Format(ErrorWordFalselyIncluded, FindWordWithMinimumLength(pdaEqualityResult.WordsInPdaAttemptButNotInPdaCorrect))); } } if (pdaEqualityResult.InconsistentWordsInPdaAttempt.Count() > 0) { grade = Math.Max(grade - 1, 0); var tuple = FindElementWithMinimumProperty(pdaEqualityResult.InconsistentWordsInPdaAttempt, t => t.Item1.Length); feedback.Add(string.Format(ErrorInconsistentAcceptanceCondition, tuple.Item1, tuple.Item2, !tuple.Item2)); } if (statesDiff > 0 || stackDiff > 0) { grade = Math.Max(0, grade - 1); if (statesDiff > 0) { feedback.Add(string.Format(ErrorToManyStates, pdaAttempt.States.Count, pdaCorrect.States.Count)); } if (stackDiff > 0) { feedback.Add(string.Format(ErrorToManyStackSymbols, stackAlphabetAttempt.Count, stackAlphabetCorrect.Count)); } } if (grade == maxGrade) { feedback.Add("Perfect!"); } else if (pdaEqualityResult.AreEqual && pdaEqualityResult.InconsistentWordsInPdaAttempt.Count() == 0) { feedback.Add("Correct (but not perfect)!"); } return(Grader.CreateXmlFeedback(grade, feedback)); }