Publication Details
Conclusive Tree-Controlled Grammars
Křivka Zbyněk, Ing., Ph.D. (DIFS FIT BUT)
Meduna Alexander, prof. RNDr., CSc. (DIFS FIT BUT)
Tree-controlled grammar, Conclusive tree-controlled grammar, Computational completeness, Derivation tree, Sub-regular language families, Descriptional complexity
This paper presents a new approach to regulation of grammars. It divides the derivation trees generated by grammars into two sectionsgenerative and conclusive (the conclusion). The former encompasses generation of symbols up till the moment when the lowest rightmost terminal of the derivation tree is generated, whereas the latter represents the final steps needed to successfully generate a sentence. A control mechanism based on regulating only the conclusion is presented and subsequently applied to tree-controlled grammars, creating conclusive tree-controlled grammars. As the main result, it is shown that the ratio between depths of generative and conclusive sections does not influence the generative power. In addition, it is demonstrated that any recursively enumerable language is generated by these grammars possessing no more than seven nonterminals while the regulating language is union-free.
@INPROCEEDINGS{FITPUB12771, author = "Dominika Klobu\v{c}n\'{i}kov\'{a} and Zbyn\v{e}k K\v{r}ivka and Alexander Meduna", title = "Conclusive Tree-Controlled Grammars", pages = "112--125", booktitle = "Proceedings 12th International Workshop on Non-Classical Models of Automata and Applications ", journal = "Electronic Proceedings in Theoretical Computer Science", number = 367, year = 2022, location = "Debrecen, HU", publisher = "School of Computer Science and Engineering, University of New South Wales", ISSN = "2075-2180", doi = "10.4204/EPTCS.367.8", language = "english", url = "https://www.fit.vut.cz/research/publication/12771" }