/// <summary>
/// Does the NFA recognize txt?
/// Returns true if the text is matched by the regular expression.
/// </summary>
/// <param name="txt">txt the text</param>
/// <returns><tt>true</tt> if the text is matched by the regular expression, <tt>false</tt> otherwise</returns>
public bool Recognizes(string txt)
{
var dfs = new DirectedDFS(_g, 0);
var pc = new Bag<Integer>();
for (var v = 0; v < _g.V; v++)
if (dfs.Marked(v)) pc.Add(v);
// Compute possible NFA states for txt[i+1]
for (var i = 0; i < txt.Length; i++)
{
var match = new Bag<Integer>();
foreach (int v in pc)
{
if (v == _m) continue;
if ((_regexp[v] == txt[i]) || _regexp[v] == '.')
match.Add(v + 1);
}
dfs = new DirectedDFS(_g, match);
pc = new Bag<Integer>();
for (var v = 0; v < _g.V; v++)
if (dfs.Marked(v)) pc.Add(v);
// optimization if no states reachable
if (pc.Size() == 0) return false;
}
// check for accept state
foreach (int v in pc)
if (v == _m) return true;
return false;
}
public void Run()
{
Console.WriteLine("Choose file:"); // Prompt
Console.WriteLine("1 - tinyDG.txt"); // Prompt
Console.WriteLine("or quit"); // Prompt
var fileNumber = Console.ReadLine();
string fileName;
switch (fileNumber)
{
case "1":
fileName = "tinyDG.txt";
break;
case "quit":
return;
default:
return;
}
var @in = new In($"Files\\Graphs\\{fileName}");
var lines = @in.ReadAllLines();
var lineIterator = 0;
var v = 0;
var e = 0;
var edges = new List<EdgeD>();
foreach (var line in lines)
{
if (lineIterator == 0)
{
v = Convert.ToInt32(line);
}
if (lineIterator == 1)
{
e = Convert.ToInt32(line);
}
if (lineIterator > 1)
{
var lineSplitted = line.Split(new[] { ' ' }, StringSplitOptions.RemoveEmptyEntries);
var ve = Convert.ToInt32(lineSplitted[0]);
var we = Convert.ToInt32(lineSplitted[1]);
var edge = new EdgeD(ve, we);
edges.Add(edge);
}
lineIterator++;
}
var digraph = new Digraph(v, e, edges);
Console.WriteLine(digraph);
Console.WriteLine("------------------------------------------------------");
var bag1 = new Core.Collections.Bag<Integer> { new Integer(1) };
var bag2 = new Core.Collections.Bag<Integer> { new Integer(2) };
var bag3 = new Core.Collections.Bag<Integer> { new Integer(1), new Integer(2), new Integer(6) };
var listSources = new List<Core.Collections.Bag<Integer>> {bag1, bag2, bag3};
foreach (var sources in listSources)
{
// multiple-source reachability
var dfs = new DirectedDFS(digraph, sources);
// print out vertices reachable from sources
for (var i = 0; i < digraph.V; i++)
{
if (dfs.Marked(i)) Console.Write($"{i} ");
}
Console.WriteLine();
Console.WriteLine("---------------------------------------------------------");
}
Console.ReadLine();
}