The covering problem for linear context-free grammars
نویسندگان
چکیده
منابع مشابه
Normal forms for linear displacement context-free grammars
In this paper we prove several results on normal forms for linear displacement context-free grammars. The results themselves are rather simple and use well-known techniques, but they are extensively used in more complex constructions. Therefore this article mostly serves educational and referential purposes. 1 Displacement context-free grammars Displacement context-free grammars (DCFGs) are a r...
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15 صفحه اولModularized Context-Free Grammars
Given two context-free grammars (CFGs), G 1 and G 2 , the language generated by the union of the grammars is not the union of the languages generated by each grammar: L(G 1 G 2) 6 = L(G 1) L(G 2). In order to account for mod-ularity of grammars, another way of deening the meaning of grammars is needed. This paper adapts results from the semantics of logic programming languages to CFGs. We discu...
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Multiple context-free grammar (MCFG) is a weakly contextsensitive grammar formalism that deals with tuples of strings. An MCFG is called m-MCFG if all tuples have at most m components. In this summary I will outline that the expressivity of m-MCFG’s increases with the parameter m and that the class of tree-adjoining languages is properly included in the class of 2-multiple context-free language...
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Graph grammars have been studied by several authors. The motivations of these works have arisen from completely different areas of computer science, such as picture processing (Pfaltz and Rosenfeld, 1969; Montanari, 1970; Rosenfeld and Milgram, 1972; Pavlidis, 1972; Abe et al., 1973; Furtado and Mylopoulos, 1975; Fu and Brayer, 1975) or formal semantics of programming languages (Pratt, 1971). I...
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ژورنال
عنوان ژورنال: Theoretical Computer Science
سال: 1976
ISSN: 0304-3975
DOI: 10.1016/0304-3975(76)90088-8