On the descriptional complexity of scattered context grammars
نویسنده
چکیده
This paper proves that every recursively enumerable language is generated by a scattered context grammar with no more than four nonterminals and three non-context-free productions. In its conclusion, it gives an overview of the results and open problems concerning scattered context grammars and languages.
منابع مشابه
On Descriptional Complexity of Partially Parallel Grammars
This paper presents some new results concerning the descriptional complexity of partially parallel grammars. Specifically, it proves that every recursively enumerable language is generated (i) by a four-nonterminal scattered context grammar with no more than four non-context-free productions, (ii) by a two-nonterminal multisequential grammar with no more than two selectors, or (iii) by a three-...
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ورودعنوان ژورنال:
- Theor. Comput. Sci.
دوره 410 شماره
صفحات -
تاریخ انتشار 2009