, and if so, then properly, in the Boolean closure of the deterministic context-free languages. ... There are nondeterministic context-free languages that cannot be expressed as a Boolean formula over deterministic context-free languages. ... , and if so, then properly, in the Boolean closure of the deterministic context-free languages. ...doi:10.1016/0022-0000(78)90030-2 fatcat:gj4dxcykc5dhbaly6mcyo5gmzu
The paper presents some automata and logics on ω-words, which capture all ω-regular languages, and yet still have good closure and decidability properties. ... It can be described using automata, namely by nondeterministic Büchi automata, or the equivalent deterministic Muller automata. ... Each of the classes captures all the ω-regular languages, and more. ...doi:10.4230/lipics.stacs.2010.2440 dblp:conf/stacs/Bojanczyk10 fatcat:6oaslsh6kndxzixfk6zzpwqj7m
The class of languages accepted by deterministic multipass automata is exactly the Boolean closure of the class of deterministic context-free languages while the class of languages accepted by nondeterministic ... multipass automata is exactly the class of poly-context-free languages, that is, languages which are the intersection of finitely many context-free languages. ... We wish to thank Ralph Strebel for very helpful discussions and his interest in our work as well as for some simplifications of an earlier version of the proof of Theorem 7.1. ...arXiv:1404.7442v4 fatcat:4sybtgehbva5hhaj6tzihf3kje
Third, for quantitative languages L1 and L2, we consider the operations max(L1, L2), min(L1, L2), and 1 − L1, which generalize the boolean operations on languages, as well as the sum L1 + L2. ... We establish the closure properties of all classes of quantitative languages with respect to these four operations. * ... We thank Wolfgang Thomas for pointing out the isolated cut-point problem. ...doi:10.1109/lics.2009.16 dblp:conf/lics/ChatterjeeDH09 fatcat:s452y64mlfegdh2c4omt3visdy
of all context-free languages; (c) the union closure of the class of complements of context-free languages; (d) the Boolean closure of the class of deterministic context-free languages. ... Also, every pda-degree language is in the Boolean closure of the class of context-free languages. ...
The intersection-closures of the deterministic and nondeterministic context-free languages are not principal AFDL’s.” ... in the Boolean closure of the context-free languages. ...
in the Boolean closure of the context-free (context-sensitive) languages. ... The class of degree-languages over pushdown automata (linear bounded automata) contains the intersection-closure and the complements of the context-free (context-sensitive) languages and it is contained ... Moreover, the Boolean closure of the deterministic context-free languages is properly contained in the pda-degree-languages. ...doi:10.1016/s0022-0000(77)80012-3 fatcat:bwvxnqcrxrhvbb3skz5bmge4mu
The value of a word w is the supremum of the values of the runs over w. We study expressiveness and closure questions about these quantitative languages. ... Third, for quantitative languages L_1 and L_2, we consider the operations (L_1,L_2), (L_1,L_2), and -L_1, which generalize the boolean operations on languages, as well as the sum L_1 + L_2. ... We thank Wolfgang Thomas for pointing out the isolated cut-point problem. ...doi:10.2168/lmcs-6(3:10)2010 fatcat:52egwusycrb7likdnggu3dmcs4
Third, for quantitative languages L_1 and L_2, we consider the operations (L_1,L_2), (L_1,L_2), and 1-L_1, which generalize the boolean operations on languages, as well as the sum L_1 + L_2. ... We establish the closure properties of all classes of quantitative languages with respect to these four operations. ... We thank Wolfgang Thomas for pointing out the isolated cut-point problem. ...arXiv:0905.2195v1 fatcat:j7zclnarwrdehdjwk4tiz4doha
are properly included in the nondeterministic iterated pushdown languages; the counter example is a very simple linear context-free language, independent of the amount of iteration, (3) LL(k) iterated ... The general notion of look-ahead on pushdowns is used to prove that (1) the deterministic iterated pushdown languages are closed under complementation, (2) the deterministic iterated pushdown languages ... (P) = CF is the class of context-free languages, and !&(P) is the class of deterministic context-free languages. ...doi:10.1016/0890-5401(87)90014-9 fatcat:yqo7xbq65bbohirb5esp7u7y5u
E 10181 Combination and decomposition of context-free grammars. ... Due to the algebraic approach and the rejection of the apparatus of first-order logic, the given proposal for the semantic analyses of context-free substantive fragments of natural languages [the author ...
Preliminaries Let A benote the empty work, 1~1 the length of a word V, and vR its reversal. For a language A let Co-A be its complement. ( Let 55'9 denote the class of context-free languages. ... As a further consequence, we get a new common upper bound for the context-free languages and the logarithmic oracle hierarchy. ...doi:10.1016/0304-3975(88)90025-4 fatcat:ncxju5tklrhlvhdkw427wjd2ky
Lecture Notes in Computer Science
For each regular language L we describe a family of canonical nondeterministic acceptors (nfas). ... Their construction follows a uniform recipe: build the minimal dfa for L in a locally finite variety V, and apply an equivalence between the finite V-algebras and a category of finite structured sets and ... It is well-known that the difficulty of this task depends on whether one has deterministic or nondeterministic acceptors in mind. ...doi:10.1007/978-3-662-44124-4_11 fatcat:egidmvatbvbc7g22gypnnudjh4
Lecture Notes in Computer Science
In this context I urge the reader to consult the paper "Programming languages, natural languages, and mathematics" by Peter Naur [ 2]. ... In the last fifteen years the area of formal language theory and abstract automata has enjoyed a great deal of attention from the research community in theoretical computer science. ... Turing machines, the intersection closure of the class of context-free languages. ...doi:10.1007/3-540-07407-4_1 fatcat:64fovopjqzgftlykgg3b3sixhy
Concerning the closure properties most of the deterministic language families studied are not closed under standard operations. ... We investigate the computational capacities of these three types of automata and their deterministic variants, comparing any of the six classes of automata with each other and with further classes of well-known ... A proper superclass of regular languages is the family of deterministic context-free languages (DCFL). ...doi:10.1016/j.ic.2009.03.002 fatcat:vyxgwbmt7reenlyumew7vju6lm
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