About: Self-verifying finite automaton

In automata theory, a self-verifying finite automaton (SVFA)is a special kind of a nondeterministic finite automaton (NFA)with a symmetric kind of nondeterminismintroduced by Hromkovič and Schnitger.Generally, in self-verifying nondeterminism,each computation path is concluded with any of the three possible answers:yes, no, and I do not know.For each input string, no two pathsmay give contradictory answers,namely both answers yes and no on the same input are not possible.At least one path must give answer yes or no,and if it is yes then the string is considered accepted.SVFA accept the same class of languages as deterministic finite automata (DFA)and NFA but have different state complexity.