public static void One(RegExp regExp, ref Automaat <string> automaat, ref int stateCounter, int leftState, int rightState)
{
char[] characters = regExp.Terminals.ToCharArray();
if (characters.Length == 1)
{
automaat.AddTransition(
new Transition <string>(leftState.ToString(), characters[0], rightState.ToString()));
}
else
{
automaat.AddTransition(
new Transition <string>(leftState.ToString(), characters[0], stateCounter.ToString()));
int i = 1;
while (i < characters.Length - 1)
{
automaat.AddTransition(new Transition <string>(stateCounter.ToString(), characters[i],
(stateCounter + 1).ToString()));
stateCounter++;
i++;
}
automaat.AddTransition(
new Transition <string>(stateCounter.ToString(), characters[i], rightState.ToString()));
stateCounter++;
}
}
private static Dictionary <char, string> SetupMerge(Automaat <string> dfaA, Automaat <string> dfaB)
{
Dictionary <char, string> completeMergedState = new Dictionary <char, string>();
foreach (string startState in dfaA.StartStates)
{
if (!completeMergedState.ContainsKey('A'))
{
completeMergedState.Add('A', startState + "_");
}
else
{
completeMergedState['A'] = completeMergedState['A'] + startState + "_";
}
}
foreach (string startState in dfaB.StartStates)
{
if (!completeMergedState.ContainsKey('B'))
{
completeMergedState.Add('B', startState + "_");
}
else
{
completeMergedState['B'] = completeMergedState['B'] + startState + "_";
}
}
completeMergedState['A'] = completeMergedState['A'].TrimEnd('_');
completeMergedState['B'] = completeMergedState['B'].TrimEnd('_');
return(completeMergedState);
}
private static Automaat <string> RetrieveDfaFromPartitions(SortedSet <Partition> partitions,
SortedSet <char> symbols)
{
Automaat <string> automaat = new Automaat <string>(symbols);
foreach (Partition p in partitions)
{
if (p.IsFinal)
{
automaat.DefineAsFinalState(p.Identifier.ToString());
}
if (p.IsStart)
{
automaat.DefineAsStartState(p.Identifier.ToString());
}
foreach (KeyValuePair <string, Row> row in p.Rows)
{
foreach (KeyValuePair <char, string> innerRow in row.Value.InnerRows)
{
string toState = "";
foreach (Partition p2 in partitions)
{
if (p2.ContainsState(innerRow.Value))
{
toState = p2.Identifier.ToString();
break;
}
}
automaat.AddTransition(new Transition <string>(p.Identifier.ToString(), innerRow.Key, toState));
}
}
}
return(automaat);
}
public static void Convert(RegExp regExp, ref Automaat <string> automaat, ref int stateCounter, int leftState, int rightState)
{
switch (regExp.Operator)
{
case RegExp.OperatorEnum.Plus:
Plus(regExp, ref automaat, ref stateCounter, leftState, rightState);
break;
case RegExp.OperatorEnum.Star:
Star(regExp, ref automaat, ref stateCounter, leftState, rightState);
break;
case RegExp.OperatorEnum.Or:
Or(regExp, ref automaat, ref stateCounter, leftState, rightState);
break;
case RegExp.OperatorEnum.Dot:
Dot(regExp, ref automaat, ref stateCounter, leftState, rightState);
break;
case RegExp.OperatorEnum.One:
One(regExp, ref automaat, ref stateCounter, leftState, rightState);
break;
}
}
public static void Dot(RegExp regExp, ref Automaat <string> automaat, ref int stateCounter, int leftState, int rightState)
{
int midState = stateCounter;
stateCounter++;
Convert(regExp.Left, ref automaat, ref stateCounter, leftState, midState);
Convert(regExp.Right, ref automaat, ref stateCounter, midState, rightState);
}
public static Automaat <string> OptimizeDfa(Automaat <string> dfa)
{
//Automaat<string> one = Reverse(dfa);
//Automaat<string> two = Convert(one);
//Automaat<string> three = Reverse(two);
//Automaat<string> four = Convert(three);
//return four;
return(Convert(Reverse(Convert(Reverse(dfa)))));
}
private static void contains(DfaGenerateValue param, ref Automaat <string> dfa)
{
char[] chars = param.Parameter.ToCharArray();
int stateCounter = 0;
dfa.DefineAsStartState(stateCounter.ToString());
foreach (char c in chars)
{
dfa.AddTransition(new Transition <string>(stateCounter.ToString(), c,
(stateCounter + 1).ToString()));
stateCounter = dfa.States.Count - 1;
}
dfa.DefineAsFinalState(stateCounter.ToString());
//Hardcopy states
List <string> ogStates = new List <string>();
foreach (string state in dfa.States)
{
ogStates.Add(state);
}
for (int i = 0; i < ogStates.Count; i++)
{
string state = ogStates[i];
List <Transition <string> > trans = dfa.GetTransition(state);
SortedSet <char> routesPresent = new SortedSet <char>();
foreach (Transition <string> t in trans)
{
routesPresent.Add(t.Symbol);
}
foreach (char letter in dfa.Symbols)
{
if (!routesPresent.Contains(letter) && !dfa.FinalStates.Contains(state))
{
int stateToReturnTo = backTrackForWorkingRoute(chars, letter);
dfa.AddTransition(new Transition <string>(state, letter, ogStates[stateToReturnTo]));
}
}
}
foreach (char c in dfa.Symbols)
{
foreach (string finalstate in dfa.FinalStates)
{
dfa.AddTransition(new Transition <string>(stateCounter.ToString(), c, stateCounter.ToString()));
}
}
}
private static void beginsWith(DfaGenerateValue param, ref Automaat <string> dfa)
{
char[] chars = param.Parameter.ToCharArray();
int stateCounter = 0;
dfa.DefineAsStartState(stateCounter.ToString());
foreach (char c in chars)
{
dfa.AddTransition(new Transition <string>(stateCounter.ToString(), c,
(stateCounter + 1).ToString()));
stateCounter = dfa.States.Count - 1;
}
dfa.DefineAsFinalState(stateCounter.ToString());
foreach (char c in dfa.Symbols)
{
dfa.AddTransition(new Transition <string>(stateCounter.ToString(), c, stateCounter.ToString()));
}
//Hardcopy states
SortedSet <string> ogStates = new SortedSet <string>();
foreach (string state in dfa.States)
{
ogStates.Add(state);
}
foreach (string state in ogStates)
{
List <Transition <string> > trans = dfa.GetTransition(state);
SortedSet <char> routesPresent = new SortedSet <char>();
foreach (Transition <string> t in trans)
{
routesPresent.Add(t.Symbol);
}
foreach (char letter in dfa.Symbols)
{
if (!routesPresent.Contains(letter))
{
dfa.AddTransition(new Transition <string>(state, letter, "F"));
}
}
}
if (dfa.States.Contains("F"))
{
foreach (char letter in dfa.Symbols)
{
dfa.AddTransition(new Transition <string>("F", letter, "F"));
}
}
}
public static Automaat <string> MinimizeDfa(Automaat <string> automaat)
{
SortedSet <Partition> partitions = new SortedSet <Partition>();
Partition nonFinals = new Partition('A');
Partition finals = new Partition('B');
// Setup first step of minimalisation (ready given Automaat for the recursion method
SortedSet <string> states = automaat.States;
foreach (string state in states)
{
List <Transition <string> > trans = automaat.GetTransition(state);
Row row = new Row();
foreach (Transition <string> t in trans)
{
row.AddRoute(t.Symbol, t.ToState);
}
if (automaat.FinalStates.Contains(state))
{
finals.AddRow(state, row);
}
else
{
nonFinals.AddRow(state, row);
}
}
partitions.Add(nonFinals);
partitions.Add(finals);
// Enter minimizing recursion
partitions = MinimizePartitions(partitions);
// Define start and final states
foreach (Partition p in partitions)
{
foreach (string finalState in automaat.FinalStates)
{
if (p.ContainsState(finalState))
{
p.IsFinal = true;
}
}
foreach (string startState in automaat.StartStates)
{
if (p.ContainsState(startState))
{
p.IsStart = true;
}
}
}
return(RetrieveDfaFromPartitions(partitions, automaat.Symbols));
}
public static void Plus(RegExp regExp, ref Automaat <string> automaat, ref int stateCounter, int leftState, int rightState)
{
int stateTwo = stateCounter;
int stateThree = stateCounter + 1;
stateCounter = stateCounter + 2;
automaat.AddTransition(new Transition <string>(leftState.ToString(), '$', stateTwo.ToString()));
automaat.AddTransition(new Transition <string>(stateThree.ToString(), '$', stateTwo.ToString()));
automaat.AddTransition(new Transition <string>(stateThree.ToString(), '$', rightState.ToString()));
Convert(regExp.Left, ref automaat, ref stateCounter, stateTwo, stateThree);
}
public static void Execute(RegExp regExp)
{
// Convert regex to ndfa
Console.WriteLine();
Console.WriteLine("----- Converting regex to ndfa -----");
Automaat <string> ndfa = ThompsonConstruction.ConvertRegExp(regExp);
foreach (Transition <string> transition in ndfa.Transitions)
{
Console.WriteLine(transition.ToString());
}
Console.WriteLine("Printing image");
GraphVizParser.PrintGraph(ndfa, "ndfa");
Console.WriteLine("Image saved as ndfa.jpg");
// Convert ndfa to dfa
Console.WriteLine();
Console.WriteLine("----- Converting ndfa to dfa -----");
Automaat <string> dfa = NdfaToDfaConverter.Convert(ndfa);
foreach (Transition <string> transition in dfa.Transitions)
{
Console.WriteLine(transition.ToString());
}
Console.WriteLine("Printing image");
GraphVizParser.PrintGraph(dfa, "dfa");
Console.WriteLine("Image saved as dfa.jpg");
// Optimizing dfa Brzozowski
Console.WriteLine();
Console.WriteLine("----- Optimizing dfa: Brzozowski's algorithm -----");
Automaat <string> brzozowskiDfa = NdfaToDfaConverter.OptimizeDfa(dfa);
foreach (Transition <string> transition in brzozowskiDfa.Transitions)
{
Console.WriteLine(transition.ToString());
}
Console.WriteLine("Printing image");
GraphVizParser.PrintGraph(brzozowskiDfa, "BrzozowskiDfa");
Console.WriteLine("Image saved as BrzozowskiDfa.jpg");
// Optimize dfa Hopcroft
Console.WriteLine();
Console.WriteLine("----- Optimizing dfa: Hopcroft's algorithm -----");
Automaat <string> hopcroftDfa = HopcroftAlgorithm.MinimizeDfa(dfa);
foreach (Transition <string> transition in hopcroftDfa.Transitions)
{
Console.WriteLine(transition.ToString());
}
Console.WriteLine("Printing image");
GraphVizParser.PrintGraph(hopcroftDfa, "HopcroftDfa");
Console.WriteLine("Image saved as HopcroftDfa.jpg");
}
private static void ConvertState(string currentState, ref Automaat <string> dfa, ref Automaat <string> ndfa)
{
//If this state is already completely processed, return to avoid stackoverflow exception
if (dfa.GetTransition(currentState).Count == ndfa.Symbols.Count)
{
return;
}
//split given state for comparison
string[] states = currentState.Split('_');
//Loop through all symbols aka all the necessary routes
foreach (char symbol in ndfa.Symbols)
{
//checks if this symbol already has a route in the new DFA
if (CheckExistingRouteForChar(currentState, symbol, dfa))
{
return;
}
int correctAmountOfRoutes = CheckAvailableRoutes(states, symbol, ndfa);
//the TOSTATE of the to be added implementation
string toState = "";
if (correctAmountOfRoutes == 0)
{
dfa.AddTransition(new Transition <string>(currentState, symbol, "F"));
}
else
{
bool isFinalState = GenerateToState(ref toState, states, symbol, ndfa);
dfa.AddTransition(new Transition <string>(currentState, symbol, toState));
//Checks if currentState is should be final aswell (could be done better)
if (ndfa.FinalStates.Contains(currentState))
{
dfa.DefineAsFinalState(currentState);
}
if (isFinalState)
{
dfa.DefineAsFinalState(toState);
}
//checks if its not a loop to itself
if (currentState != toState)
{
ConvertState(toState, ref dfa, ref ndfa);
}
}
}
}
public static Automaat <string> Reverse(Automaat <string> automaat)
{
Automaat <string> reverseAutomaat = new Automaat <string>(automaat.Symbols);
foreach (Transition <string> transition in automaat.Transitions)
{
reverseAutomaat.AddTransition(
new Transition <string>(transition.ToState, transition.Symbol, transition.FromState));
}
reverseAutomaat.StartStates = automaat.FinalStates;
reverseAutomaat.FinalStates = automaat.StartStates;
return(reverseAutomaat);
}
public static Automaat <string> ConvertRegExp(RegExp regExp)
{
Automaat <string> automaat = new Automaat <string>();
automaat.DefineAsStartState("0");
automaat.DefineAsFinalState("1");
int stateCounter = 2;
Convert(regExp, ref automaat, ref stateCounter, 0, 1);
automaat.Symbols = new SortedSet <char>(automaat.Transitions.Distinct().Select(e => e.Symbol).ToList());
//Epsilon should not be in alphabet
automaat.Symbols.Remove('$');
return(automaat);
}
public Automaat <string> Concatenation(Automaat <string> dfaA, Automaat <string> dfaB)
{
SortedSet <char> mergedAlphabet = dfaA.Symbols;
mergedAlphabet.UnionWith(dfaB.Symbols);
Automaat <string> merged = new Automaat <string>(mergedAlphabet);
Dictionary <char, string> completeMergedState = SetupMerge(dfaA, dfaB);
AddMergedState(completeMergedState, ref merged, dfaA, dfaB, MergeType.Concatenation);
// Add new state to merged, work recursively from there
return(finaliseMerge(merged));
}
public static void Or(RegExp regExp, ref Automaat <string> automaat, ref int stateCounter, int leftState, int rightState)
{
int state2 = stateCounter;
int state3 = stateCounter + 1;
int state4 = stateCounter + 2;
int state5 = stateCounter + 3;
stateCounter = stateCounter + 4;
automaat.AddTransition(new Transition <string>(leftState.ToString(), '$', state2.ToString()));
automaat.AddTransition(new Transition <string>(leftState.ToString(), '$', state4.ToString()));
automaat.AddTransition(new Transition <string>(state3.ToString(), '$', rightState.ToString()));
automaat.AddTransition(new Transition <string>(state5.ToString(), '$', rightState.ToString()));
Convert(regExp.Left, ref automaat, ref stateCounter, state2, state3);
Convert(regExp.Right, ref automaat, ref stateCounter, state4, state5);
}
public static Automaat <string> Convert(Automaat <string> ndfa)
{
Automaat <string> dfa = new Automaat <string>(ndfa.Symbols);
string combinedStartState = "";
SortedSet <string> completeStartState = new SortedSet <string>();
bool isFinalState = false;
// Loop through all the available start states from the ndfa and create a list with them + their epsilon-linked states
foreach (string startState in ndfa.StartStates)
{
RetrieveEpsilonIncludedState(startState, ndfa, ref completeStartState);
}
//Turn sortedset into a string with all its states
foreach (string s in completeStartState)
{
combinedStartState += s + "_";
if (ndfa.FinalStates.Contains(s))
{
isFinalState = true;
}
}
//trim last "_" off of string
combinedStartState = combinedStartState.TrimEnd('_');
//Start conversion
ConvertState(combinedStartState, ref dfa, ref ndfa);
// Define combinedStartState as one and only start state in dfa
dfa.DefineAsStartState(combinedStartState);
if (isFinalState)
{
dfa.DefineAsFinalState(combinedStartState);
}
// Add a symbol loop to the failstate if one is created during conversion.
if (dfa.States.Contains("F"))
{
foreach (char route in dfa.Symbols)
{
dfa.AddTransition(new Transition <string>("F", route, "F"));
}
}
return(finaliseConversion(dfa));
}
private static int CheckAvailableRoutes(string[] states, char symbol, Automaat <string> ndfa)
{
//array which shows how many possible routes there are for each sub-state
int[] possibleRoutesPerState = new int[states.Length];
//// value that shows the amount of routes the ndfa has for all the substates combined.
int correctAmountOfRoutes = 0;
//reads ndfa for possible routes, saves maximum amount of accessible routes to correctAmountOfRoutes
foreach (string state in states)
{
if (ndfa.GetTransition(state).Count(transition => transition.Symbol == symbol) > correctAmountOfRoutes)
{
correctAmountOfRoutes = ndfa.GetTransition(state).Count(transition => transition.Symbol == symbol);
}
}
return(correctAmountOfRoutes);
}
public static Automaat <string> GenerateDfa(DfaGenerateValue param, char[] symbols)
{
Automaat <string> dfa = new Automaat <string>(symbols);
if (param.Parameter == "")
{
return(null);
}
///Check alphabet and parameter
foreach (char c in param.Parameter.ToCharArray())
{
if (!dfa.Symbols.Contains(c))
{
return(null);
}
}
switch (param.Type)
{
case GeneratorType.BeginsWith:
beginsWith(param, ref dfa);
break;
case GeneratorType.Contains:
contains(param, ref dfa);
break;
case GeneratorType.EndsWith:
endsWith(param, ref dfa);
break;
}
if (param.IsNot)
{
return(Not(dfa));
}
else
{
return(dfa);
}
}
public static Automaat <string> Not(Automaat <string> automaat)
{
Automaat <string> notAutomaat = new Automaat <string>(automaat.Symbols);
//save way of copying transitions
notAutomaat.StartStates = automaat.StartStates;
foreach (Transition <string> t in automaat.Transitions)
{
notAutomaat.AddTransition(t);
}
foreach (string state in notAutomaat.States)
{
if (!automaat.FinalStates.Contains(state))
{
notAutomaat.DefineAsFinalState(state);
}
}
return(notAutomaat);
}
public static void PrintGraph(Automaat <string> data, string filename)
{
string toPrint = "";
toPrint += "digraph{";
toPrint += " ";
toPrint += "{ node[style = invis, shape = none, label = \" \", width = 0, height = 0] SSS }";
toPrint += " ";
toPrint += "node [shape = doublecircle];";
ISet <Transition <string> > transitions = data.Transitions;
SortedSet <string> finalStates = data.FinalStates;
SortedSet <string> startStates = data.StartStates;
foreach (string t in finalStates)
{
toPrint += " " + ("S" + t) + " ";
}
toPrint += "; ";
toPrint += " ";
toPrint += "node [shape = circle];";
foreach (string state in startStates)
{
toPrint += " " + ("SSS") + "-> " + ("S" + state);
}
foreach (Transition <string> t in transitions)
{
toPrint += " " + ("S" + t.FromState) + " -> " + ("S" + t.ToState) + " " + "[ label = " + "\"" +
t.Symbol + "\"" + " ];";
}
toPrint += " }";
Console.WriteLine(toPrint);
GenerateGraphFile(toPrint, filename);
}
private static void RetrieveEpsilonIncludedState(string state, Automaat <string> auto,
ref SortedSet <string> subStateList)
{
//Add given state to the given substatelist
subStateList.Add(state);
//retrieve the list of transitions from the given state
List <Transition <string> > trans = auto.GetTransition(state);
//Loop through all the transitions in search of epsilon routes. If a epsilon route is found that is not yet included in the list the route and its subsequent epsilon routes-
//Will be added to substatelist through recursion.
foreach (Transition <string> t in trans)
{
if (t.Symbol == '$' && !subStateList.Contains(t.ToState))
{
RetrieveEpsilonIncludedState(t.ToState, auto, ref subStateList);
}
}
/////Handy should we ever need to remove duplicates from an array without the use of sortedset<>
//string[] individualSubStates = (completeState.Split('_')).Distinct().ToArray();
}
private static Automaat <string> finaliseMerge(Automaat <string> merged)
{
Automaat <string> finalisedMerge = new Automaat <string>(merged.Symbols);
foreach (Transition <string> t in merged.Transitions)
{
finalisedMerge.AddTransition(new Transition <string>(t.FromState.Replace("_", String.Empty), t.Symbol, t.ToState.Replace("_", String.Empty)));
}
foreach (string startState in merged.StartStates)
{
finalisedMerge.DefineAsStartState(startState.Replace("_", String.Empty));
}
foreach (string finalState in merged.FinalStates)
{
finalisedMerge.DefineAsFinalState(finalState.Replace("_", String.Empty));
}
return(finalisedMerge);
}
private static void ConstructDfa()
{
Console.WriteLine("Please enter DFA alphabet");
string alphabet = Console.ReadLine();
Console.WriteLine("DFA should:");
Console.WriteLine("Select option");
Console.WriteLine("1: Begin with");
Console.WriteLine("2: Not begin with");
Console.WriteLine("3: No begin with rule");
ConsoleKeyInfo optionInfo = Console.ReadKey();
char beginWithOption = optionInfo.KeyChar;
Console.WriteLine("");
if (!ValidDfaOption(beginWithOption))
{
Console.WriteLine("Invalid/Incorrect parameters entered, try again");
return;
}
Console.WriteLine("Enter line");
string beginWith = Console.ReadLine();
Console.WriteLine("Select option");
Console.WriteLine("1: Contain");
Console.WriteLine("2: Not contain");
Console.WriteLine("3: No contain rule");
optionInfo = Console.ReadKey();
char containOption = optionInfo.KeyChar;
Console.WriteLine("");
if (!ValidDfaOption(containOption))
{
Console.WriteLine("Invalid/Incorrect parameters entered, try again");
return;
}
Console.WriteLine("Enter line");
string contain = Console.ReadLine();
Console.WriteLine("Select option");
Console.WriteLine("1: End with");
Console.WriteLine("2: Not end with");
Console.WriteLine("3: No end with rule");
optionInfo = Console.ReadKey();
char endWithOption = optionInfo.KeyChar;
Console.WriteLine("");
if (!ValidDfaOption(endWithOption))
{
Console.WriteLine("Invalid/Incorrect parameters entered, try again");
return;
}
Console.WriteLine("Enter line");
string endWith = Console.ReadLine();
Automaat <string> .DfaGenerateValue param1;
Automaat <string> .DfaGenerateValue param2;
Automaat <string> .DfaGenerateValue param3;
Automaat <string> part1 = null;
Automaat <string> part2 = null;
Automaat <string> part3 = null;
List <Automaat <string> > setupParts = new List <Automaat <string> >();
if (beginWith != "" && beginWithOption != '3')
{
if (beginWithOption == '1')
{
param1 = new Automaat <string> .DfaGenerateValue
{
Parameter = beginWith,
IsNot = false,
Type = Automaat <string> .GeneratorType.BeginsWith
};
part1 = Automaat <string> .GenerateDfa(param1, alphabet.ToCharArray());
}
if (beginWithOption == '2')
{
param1 = new Automaat <string> .DfaGenerateValue
{
Parameter = beginWith,
IsNot = true,
Type = Automaat <string> .GeneratorType.BeginsWith
};
part1 = Automaat <string> .GenerateDfa(param1, alphabet.ToCharArray());
}
if (part1 == null)
{
Console.WriteLine("Invalid/Incorrect parameters entered, try again");
return;
}
setupParts.Add(part1);
}
if (contain != "" && containOption != '3')
{
if (containOption == '1')
{
param2 = new Automaat <string> .DfaGenerateValue
{
Parameter = contain,
IsNot = false,
Type = Automaat <string> .GeneratorType.Contains
};
part2 = Automaat <string> .GenerateDfa(param2, alphabet.ToCharArray());
}
if (containOption == '2')
{
param2 = new Automaat <string> .DfaGenerateValue
{
Parameter = contain,
IsNot = true,
Type = Automaat <string> .GeneratorType.Contains
};
part2 = Automaat <string> .GenerateDfa(param2, alphabet.ToCharArray());
}
if (part2 == null)
{
Console.WriteLine("Invalid/Incorrect parameters entered, try again");
return;
}
setupParts.Add(part2);
}
if (endWith != "" && beginWithOption != '3')
{
if (endWithOption == '1')
{
param3 = new Automaat <string> .DfaGenerateValue
{
Parameter = endWith,
IsNot = false,
Type = Automaat <string> .GeneratorType.EndsWith
};
part3 = Automaat <string> .GenerateDfa(param3, alphabet.ToCharArray());
}
if (beginWithOption == '2')
{
param3 = new Automaat <string> .DfaGenerateValue
{
Parameter = endWith,
IsNot = true,
Type = Automaat <string> .GeneratorType.EndsWith
};
part3 = Automaat <string> .GenerateDfa(param3, alphabet.ToCharArray());
}
if (part3 == null)
{
Console.WriteLine("Invalid/Incorrect parameters entered, try again");
return;
}
setupParts.Add(part3);
}
;
;
Automaat <string> toUse = null;
;
if (setupParts.Count == 1)
{
toUse = setupParts[0];
}
else if (setupParts.Count == 2)
{
toUse = Automaat <string> .Union(setupParts[0], setupParts[1]);
}
else if (setupParts.Count == 3)
{
Automaat <string> takeOne = Automaat <string> .Union(setupParts[0], setupParts[1]);
Automaat <string> takeTwo = Automaat <string> .Union(takeOne, setupParts[2]);
toUse = takeTwo;
}
if (toUse != null)
{
Console.WriteLine("----- DFA generated -----");
foreach (Transition <string> transition in toUse.Transitions)
{
Console.WriteLine(transition.ToString());
}
Console.WriteLine("Printing image");
GraphVizParser.PrintGraph(toUse, "DFA");
Console.WriteLine("Image saved as DFA.jpg");
Console.WriteLine();
Console.WriteLine("----- Optimizing custom DFA: Brzozowski's algorithm -----");
Automaat <string> brzozowskiDfa = NdfaToDfaConverter.OptimizeDfa(toUse);
foreach (Transition <string> transition in brzozowskiDfa.Transitions)
{
Console.WriteLine(transition.ToString());
}
Console.WriteLine("Printing image");
GraphVizParser.PrintGraph(brzozowskiDfa, "BrzozowskiDFA");
Console.WriteLine("Image saved as BrzozowskiDFA.jpg");
// Optimize dfa Hopcroft
Console.WriteLine();
Console.WriteLine("----- Optimizing custom DFA: Hopcroft's algorithm -----");
Automaat <string> hopcroftDfa = HopcroftAlgorithm.MinimizeDfa(toUse);
foreach (Transition <string> transition in hopcroftDfa.Transitions)
{
Console.WriteLine(transition.ToString());
}
Console.Write("Amount of states in hopcroft DFA: ");
Console.WriteLine(hopcroftDfa.States.Count);
Console.WriteLine("Printing image");
GraphVizParser.PrintGraph(hopcroftDfa, "HopcroftDFA");
Console.WriteLine("Image saved as HopcroftDFA.jpg");
if (hopcroftDfa.States.Count > 25)
{
Console.WriteLine("[Warning] This hopcroft dfa has more than 25 states.");
Console.WriteLine("Due to char(ASCII) limitations, parsing issues could arise with printing this dfa correctly to an image");
Console.WriteLine("This is a third-party library (Graphviz) related issue");
Console.WriteLine("The above shown list of transitions from this hopcroft dfa ARE STILL CORRECT however");
}
}
else
{
Console.WriteLine("Invalid/Incorrect parameters entered, try again");
}
//Automaat<string> takeOne = Automaat<string>.Union(part1, part2);
//Automaat<string> takeTwo = Automaat<string>.Union(takeOne, part3);
//GraphVizParser.PrintGraph(toUse, "customDfa");
}
//Fills toState string with correct TOSTATE, returns true or false whether or not this new TOSTATE should be a final state
private static bool GenerateToState(ref string toState, string[] states, char symbol, Automaat <string> ndfa)
{
//boolean that will save whether this new TOSTATE needs to be a finalstate
bool isFinalState = false;
//Set of all the substates that need to be combined. this set does also include all states reached through epsilon routes
SortedSet <string> newStates = new SortedSet <string>();
//Loop through all the substates
foreach (string state in states)
{
//ndfa transitions for state
List <Transition <string> > trans = ndfa.GetTransition(state);
//This loop goes through all the aforementioned transitions
//to see if there are routes with the correct symbol that need to be added to the new TOSTATE
foreach (Transition <string> t in trans)
{
if (t.Symbol == symbol)
{
RetrieveEpsilonIncludedState(t.ToState, ndfa, ref newStates);
//DEPRECATED, does not work if finalstate is reached through epsilon routes
//Check if this state is final, if one of the substates for the new TOSTATE is final, TOSTATE becomes final as a whole.
//if (ndfa.FinalStates.Contains(t.ToState))
//{
// isFinalState = true;
//}
}
}
}
//combines substates into one string (TOSTATE)
foreach (string subState in newStates)
{
toState += subState + "_";
if (ndfa.FinalStates.Contains(subState))
{
isFinalState = true;
}
}
toState = toState.TrimEnd('_');
return(isFinalState);
}
private static void AddMergedState(Dictionary <char, string> prevMergedState, ref Automaat <string> merged, Automaat <string> dfaA, Automaat <string> dfaB, MergeType type)
{
// string[] states = prevMergedState.Split('_');
// Add prev
int countFinal = 0;
int countStart = 0;
string completePrevMergedState = "";
foreach (KeyValuePair <char, string> entry in prevMergedState)
{
completePrevMergedState += entry.Value + "_";
if (entry.Key == 'A')
{
if (dfaA.FinalStates.Contains(entry.Value))
{
countFinal++;
}
if (dfaA.StartStates.Contains(entry.Value))
{
countStart++;
}
}
else if (entry.Key == 'B')
{
if (dfaB.FinalStates.Contains(entry.Value))
{
countFinal++;
}
if (dfaB.StartStates.Contains(entry.Value))
{
countStart++;
}
}
}
completePrevMergedState = completePrevMergedState.TrimEnd('_');
if (type == MergeType.Union && countFinal == prevMergedState.Count)
{
merged.DefineAsFinalState(completePrevMergedState);
}
else if (type == MergeType.Concatenation && countFinal >= 1)
{
merged.DefineAsFinalState(completePrevMergedState);
}
if (type == MergeType.Union && countStart == prevMergedState.Count)
{
merged.DefineAsStartState(completePrevMergedState);
}
else if (type == MergeType.Concatenation && countStart >= 1)
{
merged.DefineAsStartState(completePrevMergedState);
}
if (merged.GetTransition(completePrevMergedState).Count == merged.Symbols.Count)
{
return;
}
foreach (char symbol in merged.Symbols)
{
Dictionary <char, string> newMergedState = new Dictionary <char, string>();
// This could break though
if (CheckExistingRouteForChar(completePrevMergedState, symbol, merged))
{
return;
}
foreach (KeyValuePair <char, string> entry in prevMergedState)
{
if (entry.Key == 'A')
{
CollectRoutesFromDfa(entry, symbol, dfaA, ref newMergedState);
}
else if (entry.Key == 'B')
{
CollectRoutesFromDfa(entry, symbol, dfaB, ref newMergedState);
}
}
string completeNewMergedState = "";
foreach (KeyValuePair <char, string> entry in newMergedState)
{
completeNewMergedState += entry.Value + "_";
}
completeNewMergedState = completeNewMergedState.TrimEnd('_');
merged.AddTransition(new Transition <string>(completePrevMergedState, symbol, completeNewMergedState));
AddMergedState(newMergedState, ref merged, dfaA, dfaB, type);
}
}
private static void CollectRoutesFromDfa(KeyValuePair <char, string> entry, char symbol, Automaat <string> source,
ref Dictionary <char, string> newMergedState)
{
string[] states = entry.Value.Split('_');
foreach (string state in states)
{
List <Transition <string> > trans = source.GetTransition(state);
foreach (Transition <string> t in trans)
{
if (t.Symbol == symbol)
{
if (!newMergedState.ContainsKey(entry.Key))
{
newMergedState.Add(entry.Key, t.ToState + "_");
}
else
{
newMergedState[entry.Key] = newMergedState[entry.Key] + t.ToState + "_";
}
}
}
///TEST THIS
if (newMergedState.ContainsKey(entry.Key))
{
newMergedState[entry.Key] = newMergedState[entry.Key].TrimEnd('_');
}
}
}
private static bool CheckExistingRouteForChar(string currentState, char symbol, Automaat <string> dfa)
{
List <Transition <string> > currentTrans = dfa.GetTransition(currentState);
foreach (Transition <string> t in currentTrans)
{
if (t.Symbol == symbol)
{
return(true);
}
}
return(false);
}
