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Page 3494 of Mathematical Reviews Vol. , Issue 94f [page]

1994 Mathematical Reviews  
test sets for regular and context-free languages.  ...  The constructions given also imply new time bounds for (1) the morphism equality problem for regular languages (given a regular language L and two morphisms / and g, does g(x) = h(x) hold for each x in  ... 

Combinatorial and Algorithmic Aspects of Sequence Processing (Dagstuhl Seminar 11081)

Maxime Crochemore, Lila Kari, Mehryar Mohri, Dirk Nowotka, Marc Herbstritt
2011 Dagstuhl Reports  
Combinatorial problems about strings lie at the core of such algorithmic questions.  ...  Algorithms to efficiently search through, analyze, (de-)compress, match, learn, and encode/decode strings are therefore of chief interest.  ...  Problem: estimate the growth of the language of the k-ary RT (k) + -free language. Exponential conjecture (folklore): all these languages have exponential growth. Confirmed by Ochem for k = 3, 4.  ... 
doi:10.4230/dagrep.1.2.47 dblp:journals/dagstuhl-reports/CrochemoreKMN11 fatcat:s3v55bqr4fbdfo5kztirfoljqm

Page 810 of Mathematical Reviews Vol. , Issue 82b [page]

1982 Mathematical Reviews  
Various straightforward hierarchy results are obtained for families ((£,,2,) with ©, and &, different well-known subfamilies of context-free languages (m-linear, regular, finite, singleton).  ...  Among these predicates are the multiplicative and nonerasing properties, equivalence to an OL scheme and closure under extraction of roots for regular languages. A. V.  ... 

Page 7660 of Mathematical Reviews Vol. , Issue 95m [page]

1995 Mathematical Reviews  
The decidability of many problems in- volving context-free languages is also studied.  ...  In addition, several efficient recognition algorithms for context-free languages are pre- sented in detail: (I) the CYK algorithm, which recognizes whether a word w € L(G) in cubic time, i.e. in O(|w|*  ... 

Page 324 of Mathematical Reviews Vol. 51, Issue 1 [page]

1976 Mathematical Reviews  
The author describes an original parsing algorithm for context- free languages and studies the time complexity involved. The algorithm assumes a context-free grammar in Chomsky binary normal form.  ...  Thus, for example, the classes of regular, context-free, and recursively enumerable languages are closed under £,,. It is also claimed that context-sensitive languages are closed under £,, and R,,.  ... 

Page 431 of Mathematical Reviews Vol. , Issue 91A [page]

1991 Mathematical Reviews  
Polynomial time bounds for the dgsm equivalence and the morphic replication equivalence on Q-rational languages are found by means of the result that the emptiness problem for Q-rational languages is decidable  ...  A corresponding result is derived for the morphic replication equivalence on linear languages. “The results above provide an algorithm of exponential time complexity.  ... 

Page 5102 of Mathematical Reviews Vol. , Issue 2000g [page]

2000 Mathematical Reviews  
We show that equivalence is decidable between context-free and everywhere growing DTOL languages.” 2000g:68082 68Q45 68Q42 Honkala, Juha (FIN-TURK; Turku) The equivalence problem of DOL and DFOL power  ...  Summary: “The Culik-Kari recursive inference algorithm for WFA is based on an efficient way of expressing subsquares of the given image as linear combinations of available states.  ... 

Combinatorial Characterization of Formal Languages [article]

Arseny M. Shur
2010 arXiv   pre-print
For several classes of languages, a variety of problems about combinatorial complexity and its connections to other parameters of languages are studied.  ...  This paper is an extended abstract of the dissertation presented by the author for the doctoral degree in physics and mathematics (in Russia).  ...  The corresponding decision problem is called the context equivalence problem (for the language L) 11 .  ... 
arXiv:1010.5456v1 fatcat:g7u6h6llcjdqxfjpowplr3e7oq

Cumulative index of volumes 1–50

1988 Theoretical Computer Science  
., On the equivalence problem of compositions of morphisms and inverse morphisms on context-free languages (Note) MAON, Y., B. SCHIEBER and U.  ...  HAUSSLER, On total regulators generated by derivation relations BUCHER, W. and J. HAGAUER, It is decidable whether a regular language is pure context-free (Note) BUCHER, W., H.A.  ...  return and dual return complexities WEDDE, H., An interative and starvation-free solution for a general class of distributed control problems based on interaction primitives WEDDE, H., see A.  ... 
doi:10.1016/0304-3975(88)90002-3 fatcat:gasluptczbb6bfplioxrtdrlpy

Page 725 of Mathematical Reviews Vol. , Issue 85b [page]

1985 Mathematical Reviews  
The equivalence and inclusion problems for finite and rational systems of equations are shown to be decidable and, consequently, the validity of Ehrenfeucht’s conjecture implies the decidability of the  ...  This technically impressive paper gives an intricate algorithm for deciding the equivalence problem for nonnested separable recur- sive program schemes. In earlier papers (Theoret. Comput.  ... 

On some algorithmic problems regarding the hairpin completion

Florin Manea, Carlos Martín-Vide, Victor Mitrana
2009 Discrete Applied Mathematics  
We show that the n factor is not needed in the case of hairpin completion of regular and context-free languages.  ...  A linear time algorithm for deciding whether or not the hairpin completion distance with respect to a given word is connected is also discussed.  ...  Acknowledgements The first author's work was partially supported by the Research grant ET75/2005 of the Romanian Authority for Scientific Research.  ... 
doi:10.1016/j.dam.2007.09.022 fatcat:z2voblx3jfc2nidcjmvtha33ri

THE INCLUSION PROBLEM OF CONTEXT-FREE LANGUAGES: SOME TRACTABLE CASES

ALBERTO BERTONI, CHRISTIAN CHOFFRUT, ROBERTO RADICIONI
2011 International Journal of Foundations of Computer Science  
As an application, we obtain a polynomial time algorithm for testing if a context-free language is included in a Dyck language (the best previous algorithm for this problem was doubly exponential).  ...  We study the problem of testing whether a context-free language is included in a fixed set L0, where L0 is the language of words reducing to the empty word in the monoid defined by a complete string rewrite  ...  Conclusions We studied some conditions for which the inclusion problem for context-free languages is decidable in polynomial time.  ... 
doi:10.1142/s0129054111008040 fatcat:iqu2fcconbcepmuly67ezyao3u

Reference list of indexed articles

1999 Theoretical Computer Science  
Rosenkrantz and T.G. Szymanski, The covering problem for linear context-free grammars 2 (3) (1976) 361-382 48. W.J.  ...  Culik, II, On the decidability of the sequence equivalence problem for DOL-systems 3 (1) (1976) 75-84 56. T. Araki and T.  ... 
doi:10.1016/s0304-3975(98)00320-x fatcat:bdgg2ekzdjahdo7g2gtwbdye6m

Efficient Algorithms for Morphisms over Omega-Regular Languages [article]

Lukas Fleischer, Manfred Kufleitner
2015 arXiv   pre-print
In addition, we give algorithms for efficiently solving various decision problems for weakly recognizing morphisms.  ...  Morphisms to finite semigroups can be used for recognizing omega-regular languages.  ...  Since the semigroup for a language can be exponentially bigger than its automaton, semigroups have very rarely been considered in the context of efficient algorithms.  ... 
arXiv:1509.06215v2 fatcat:tmddlly5jfeehkxlcxj4dydkni

Page 8506 of Mathematical Reviews Vol. , Issue 2002K [page]

2002 Mathematical Reviews  
2002k:68095 tic context-free languages, while the linear time complexity of the algorithm associated to the membership problem is maintained.  ...  It is the initial topology for the monoid morphisms from the free monoid into a finite discrete group.  ... 
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