public static void Main()
{
Grammar grammar;
while (true)
{
try
{
grammar = GrammarReader.ReadGrammar();
break;
}
catch
{
Console.WriteLine("Неверный формат ввода");
}
}
Console.WriteLine("Грамматика G:");
Console.Write("\nVn: { ");
for (var i = 0; i < grammar.VN.Count - 1; ++i)
{
Console.Write($"{grammar.VN[i]}, ");
}
Console.Write($"{grammar.VN.Last()} }}");
Console.Write("\nVt: { ");
for (var i = 0; i < grammar.VT.Count - 1; ++i)
{
Console.Write($"{grammar.VT[i]}, ");
}
Console.Write($"{grammar.VT.Last()} }}");
Console.WriteLine("\nПравила: ");
foreach (var rule in grammar.Rules)
{
Console.WriteLine($"{rule.LeftSide} -> {rule.RightSide}");
}
var solver = new FirstFollowFinder(grammar);
int k;
while (true)
{
Console.Write("Введите k: ");
var res = int.TryParse(Console.ReadLine(), out k);
if (res && k > 0)
{
break;
}
}
Console.WriteLine("\nFIRSTk для нетерминалов:");
var firsts = solver.FirstForNonterminal(k);
foreach (var nt in firsts.Keys)
{
Console.Write($"FIRST({nt}): {{ ");
foreach (var e in firsts[nt])
{
if (e == "ε")
{
Console.Write("epsilon");
}
else
{
Console.Write($"{e}");
}
if (firsts[nt].IndexOf(e) != firsts[nt].Count - 1)
{
Console.Write($",");
}
Console.Write(" ");
}
Console.WriteLine("}");
}
Console.WriteLine("\nFOLLOWk для нетерминалов:");
var follows = solver.FollowForNonterminal(k);
foreach (var nt in follows.Keys)
{
Console.Write($"FOLLOW({nt}): {{ ");
foreach (var e in follows[nt])
{
if (e == "ε")
{
Console.Write("epsilon");
}
else
{
Console.Write($"{e}");
}
if (follows[nt].IndexOf(e) != follows[nt].Count - 1)
{
Console.Write($",");
}
Console.Write(" ");
}
Console.WriteLine("}");
}
}
private static Dictionary <(char, char), List <List <string> > > SigmaI(Grammar g, FirstFollowFinder firstFollowFinder, int k)
{
// Строим sigma_0
var sigma_0 = new Dictionary <(char, char), List <List <string> > >();
foreach (var ntA in g.VN)
{
foreach (var ntB in g.VN)
{
sigma_0.Add((ntA, ntB), new List <List <string> >());
foreach (var rule in g.Rules)
{
if (rule.LeftSide == ntA.ToString())
{
if (rule.RightSide.Contains(ntB))
{
for (var i = 0; i < rule.RightSide.Length; ++i)
{
if (rule.RightSide[i] == ntB)
{
var alpha = rule.RightSide.Substring(i + 1, rule.RightSide.Length - i - 1);
sigma_0[(ntA, ntB)].Add(firstFollowFinder.First(k, alpha));