public static NFA CreateAutomaton(string a) { var result = new NFA(); var start = 0; var next = 1; result.AddState(start, false); for (int i = 0; i < a.Length; ++i) { if (a[i] == '*') { result.AddTransition(next - 1, next - 1, NFA.Any); } else { result.AddState(next, false); result.AddTransition(next - 1, next, (a[i] != '?' ? CharRange.SingleChar(a[i]) : NFA.Any)); ++next; } } result.AddState(next, true); result.AddTransition(next - 1, next, NFA.Epsilon); return(result); }
public static NFA CreateAutomaton(string a, int k) { if (a.Contains('*')) { throw new ArgumentException("Star is a reserved character"); } var result = new NFA(); var m = a.Length + 1; /* Create |a|*k states */ for (int i = 0; i < m; ++i) { for (int j = 0; j <= k; ++j) { result.AddState(i + m * j, i == a.Length); } } /* Create transitions */ for (int i = 0; i < m; ++i) { for (int j = 0; j <= k; ++j) { if (i < m - 1) { result.AddTransition(i + m * j, i + 1 + m * j, CharRange.SingleChar(a[i])); } if (j < k) { if (i < m - 1) { result.AddTransition(i + m * j, i + 1 + m * (j + 1), NFA.Any); result.AddTransition(i + m * j, i + 1 + m * (j + 1), NFA.Epsilon); } result.AddTransition(i + m * j, i + m * (j + 1), NFA.Any); } } } return(result); }