Abstract

Problems related to the complexity and to the decidability of several languages weaker than Prolog are studied in this paper. In particular, monadic logic programs, that is, programs containing only monadic functions and monadic predicates, are considered in detail. The functional complexity of a monadic logic program is the language of all words ƒ 1… ƒ k such that the literal p(ƒ 1(…(ƒ k(a))…)) is a logical consequence of the program. The relationship between several subclasses of monadic programs, their functional complexities and the corresponding automata is studied. It is proved that the class of monadic programs corresponds exactly to the class of regular languages. As a consequence, the “SUCCESS” problem is decidable for that class. It is also proved that the success set of a specific subclass of monadic programs (“simple” programs) corresponds exactly to regular languages with star-height not exceeding 1.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.