Abstract
Regular languages that are most complex under common complexity measures are studied. In particular, certain ternary languages U n (a,b,c), \(n\geqslant 3\), over the alphabet {a,b,c} are examined. It is proved that the state complexity bounds that hold for arbitrary regular languages are also met by the languages U n (a,b,c) for union, intersection, difference, symmetric difference, product (concatenation) and star. Maximal bounds are also met by U n (a,b,c) for the number of atoms, the quotient complexity of atoms, the size of the syntactic semigroup, reversal, and 22 combined operations, 5 of which require slightly modified versions. The language U n (a,b,c,d) is an extension of U n (a,b,c), obtained by adding an identity input to the minimal DFA of U n (a,b,c). The witness U n (a,b,c,d) and its modified versions work for 14 more combined operations. Thus U n (a,b,c) and U n (a,b,c,d) appear to be universal witnesses for alphabets of size 3 and 4, respectively.
This work was supported by the Natural Sciences and Engineering Research Council of Canada under grant No. OGP0000871.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
References
Brzozowski, J.: Quotient complexity of regular languages. J. Autom. Lang. Comb. 15(1/2), 71–89 (2010)
Brzozowski, J., Li, B.: Syntactic complexities of some classes of star-free languages. In: Proceedings of the 14th International Workshop on Descriptional Complexity of Formal Systems (DCFS). LNCS. Springer, Heidelberg (to appear, 2012)
Brzozowski, J., Li, B., Ye, Y.: Syntactic complexity of prefix-, suffix-, bifix-, and factor-free regular languages. Theoret. Comput. Sci. (in press, 2012)
Brzozowski, J., Tamm, H.: Theory of Átomata. In: Mauri, G., Leporati, A. (eds.) DLT 2011. LNCS, vol. 6795, pp. 105–116. Springer, Heidelberg (2011)
Brzozowski, J., Tamm, H.: Quotient complexity of atoms of regular languages. In: Proceedings of the 16th International Conference on Developments in Language Theory (DLT). LNCS. Springer, Heidelberg (to appear, 2012)
Brzozowski, J., Ye, Y.: Syntactic Complexity of Ideal and Closed Languages. In: Mauri, G., Leporati, A. (eds.) DLT 2011. LNCS, vol. 6795, pp. 117–128. Springer, Heidelberg (2011)
Cui, B., Gao, Y., Kari, L., Yu, S.: State complexity of two combined operations: catenation-union and catenation-intersection. Int. J. Found. Comput. Sc. 22(8), 1797–1812 (2011)
Cui, B., Gao, Y., Kari, L., Yu, S.: State complexity of combined operations with two basic operations. Theoret. Comput. Sci. 437, 82–102 (2012)
Cui, B., Gao, Y., Kari, L., Yu, S.: State complexity of two combined operations: catenation-star and catenation-reversal. Int. J. Found. Comput. Sc. 23(1), 51–66 (2012)
Dénes, J.: On transformations, transformation semigroups and graphs. In: Erdös, P., Katona, G. (eds.) Theory of Graphs. Proceedings of the Colloquium on Graph Theory held at Tihany 1966, pp. 65–75. Akadémiai Kiado (1968)
Ganyushkin, O., Mazorchuk, V.: Classical Finite Transformation Semigroups: An Introduction. Springer (2009)
Gao, Y., Kari, L., Yu, S.: State complexity of union and intersection of square and reversal on k regular languages. Theoret. Comput. Sci. (in press, 2012)
Gao, Y., Kari, L., Yu, S.: State complexity of union and intersection of star on k regular languages. Theoret. Comput. Sci. 429, 98–107 (2012)
Gao, Y., Salomaa, K., Yu, S.: The state complexity of two combined operations: star of catenation and star of reversal. Fund. Inform. 83(1-2), 75–89 (2008)
Gao, Y., Yu, S.: State complexity of combined operations with union, intersection, star, and reversal. Fund. Inform. 116, 1–12 (2012)
Jirásková, G., Okhotin, A.: On the state complexity of star of union and star of intersection. Fund. Inform. 109, 1–18 (2011)
Jirásková, G., Šebej, J.: Note on Reversal of Binary Regular Languages. In: Holzer, M., Kutrib, M., Pighizzini, G. (eds.) DCFS 2011. LNCS, vol. 6808, pp. 212–221. Springer, Heidelberg (2011)
Leiss, E.: Succinct representation of regular languages by boolean automata. Theoret. Comput. Sci. 13, 323–330 (1981)
Maslov, A.N.: Estimates of the number of states of finite automata. Dokl. Akad. Nauk SSSR 194, 1266–1268 (1970) (Russian); English translation: Soviet Math. Dokl. 11, 1373–1375 (1970)
McNaughton, R., Papert, S.A.: Counter-Free Automata. M.I.T. Research Monographs, vol. 65. The MIT Press (1971)
Mirkin, B.G.: On dual automata. Kibernetika (Kiev) 2, 7–10 (1966) (Russian); English translation: Cybernetics 2, 6–9 (1966)
Myhill, J.: Finite automata and representation of events. Wright Air Development Center Technical Report 57–624 (1957)
Piccard, S.: Sur les fonctions définies dans les ensembles finis quelconques. Fund. Math. 24, 298–301 (1935)
Pin, J.E.: Syntactic semigroups. In: Handbook of Formal Languages. Word, Language, Grammar, vol. 1, pp. 679–746. Springer, New York (1997)
Rabin, M., Scott, D.: Finite automata and their decision problems. IBM J. Res. and Dev. 3, 114–129 (1959)
Salomaa, A., Salomaa, K., Yu, S.: State complexity of combined operations. Theoret. Comput. Sci. 383, 140–152 (2007)
Salomaa, A., Wood, D., Yu, S.: On the state complexity of reversals of regular languages. Theoret. Comput. Sci. 320, 315–329 (2004)
Sierpiński, W.: Sur les suites infinies de fonctions définies dans les ensembles quelconques. Fund. Math. 24, 209–212 (1935)
Yu, S., Zhuang, Q., Salomaa, K.: The state complexities of some basic operations on regular languages. Theoret. Comput. Sci. 125, 315–328 (1994)
Yu, S.: State complexity of regular languages. J. Autom. Lang. Comb. 6, 221–234 (2001)
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2012 Springer-Verlag Berlin Heidelberg
About this paper
Cite this paper
Brzozowski, J. (2012). In Search of Most Complex Regular Languages. In: Moreira, N., Reis, R. (eds) Implementation and Application of Automata. CIAA 2012. Lecture Notes in Computer Science, vol 7381. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-31606-7_2
Download citation
DOI: https://doi.org/10.1007/978-3-642-31606-7_2
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-642-31605-0
Online ISBN: 978-3-642-31606-7
eBook Packages: Computer ScienceComputer Science (R0)