On input-revolving deterministic and nondeterministic finite automata
2009 (English)In: Information and Computation, ISSN 0890-5401, E-ISSN 1090-2651, Vol. 207, 1140-1155 p.Article in journal (Refereed) Published
We introduce and investigate input-revolving finite automata, which are (nondeterministic) finite state automata with additional ability to shift the remaining part of the input. Three different modes of shifting are considered, namely revolving to the left, revolving to the right, and circular-interchanging. We investigate the computational capacities of these three types of automata and their deterministic variants, comparing any of the six classes of automata with each other and with further classes of well-known automata. In particular, it is shown that nondeterminism is better than determinism, that is, for all three modes of shifting there is a language accepted by the nondeterministic model but not accepted by any determinstic automaton of the same type. Concerning the closure properties most of the deterministic language families studied are not closed under standard operations. For example, we show that the family of languages accepted by deterministic right-revolving finite automata is an anti-AFL which is not closed under reversal and intersection.
Place, publisher, year, edition, pages
2009. Vol. 207, 1140-1155 p.
Extended finite automata, Formal language operations, Computational power, Closure properties, Anti-abstract family of languages
IdentifiersURN: urn:nbn:se:umu:diva-31785OAI: oai:DiVA.org:umu-31785DiVA: diva2:294226