Descriptional Complexity of Grammars Regulated by Context Conditions
نویسندگان
چکیده
This paper improves several well-known results concerning the descriptional complexity of grammars regulated by context conditions. Specifically, it proves that every recursively enumerable language is generated (A) by a context-conditional grammar of degree (2, 1) with no more than seven conditional productions and eight nonterminals, (B) by a generalized forbidding grammar of degree two with no more than eight conditional productions and ten nonterminals, or (C) by a simple semi-conditional grammar of degree (2, 1) with no more than nine conditional productions and ten nonterminals.
منابع مشابه
Descriptional Complexity of Generalized Forbidding Grammars
This paper discusses the descriptional complexity of generalized forbidding grammars in context of degrees, numbers of nonterminals and conditional productions, and a new descriptional complexity measure—an index—of generalized forbidding grammars.
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