Algorithms for Kleene algebra with converse

Autor: Damien Pous, Paul Brunet
Rok vydání: 2016
Předmět:
Zdroj: Journal of Logical and Algebraic Methods in Programming. 85:574-594
ISSN: 2352-2208
DOI: 10.1016/j.jlamp.2015.07.005
Popis: The equational theory generated by all algebras of binary relations with operations of union, composition, converse and reflexive transitive closure was studied by Bernatsky, Bloom, Esik and Stefanescu in 1995. In particular, they obtained its decidability by using a particular automata construction. We show that deciding this equational theory is PSpace -complete, by providing a PSpace algorithm (the problem is easily shown to be PSpace -hard). We obtain other algorithms that are time-efficient in practice, despite not being PSpace . Our results use an alternative automata construction, inspired by the one from Bloom, Esik and Stefanescu. We relate those two constructions by exhibiting a bisimulation between the resulting deterministic automata, and by showing how our construction results in more sharing between states, thus producing smaller automata.
Databáze: OpenAIRE