Membership for growing context-sensitive grammars is polynomial
Journal of Computer and System Sciences
Church-Rosser Thue systems and formal languages
Journal of the ACM (JACM)
A closure property of regular languages (Note)
Theoretical Computer Science
String-rewriting systems
On weakly confluent monadic string-rewriting systems
STACS '91 Selected papers of the 8th annual symposium on Theoretical aspects of computer science
Context-free languages and pushdown automata
Handbook of formal languages, vol. 1
Growing context-sensitive languages and Church-Rosser languages
Information and Computation
Introduction To Automata Theory, Languages, And Computation
Introduction To Automata Theory, Languages, And Computation
Introduction to Formal Language Theory
Introduction to Formal Language Theory
McNaughton families of languages
Theoretical Computer Science
Deleting string rewriting systems preserve regularity
Theoretical Computer Science - Developments in language theory
Observation of String-Rewriting Systems
Fundamenta Informaticae - SPECIAL ISSUE MCU2004
Information and Computation
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We study the McNaughton families of languages that are specified by four different variants of monadic string-rewriting systems: strictly monadic systems, monadic systems, inverse context-free systems, and generalized monadic systems. In the general case these four variants yield the same McNaughton family of languages, which coincides with the class of context-free languages. In the case of confluent systems, however, we obtain two McNaughton families by showing that special rules, that is, rules with empty right-hand side, are not needed. This implies that in this situation strictly monadic systems are as expressive as monadic systems, and inverse context-free systems are as expressive as generalized monadic systems. The McNaughton family defined by the former systems is contained in the McNaughton family that is defined by the latter systems, and this inclusion is proper if and only if the former family is not closed under inverse alphabetic morphisms. Finally, we show that the latter family is a proper subclass of the class of deterministic context-free languages.