Abstract
Limited automata are single-tape Turing machines with severe rewriting restrictions. They have been introduced in 1967 by Thomas Hibbard, who proved that they have the same computational power as pushdown automata. Hence, they provide an alternative characterization of the class of context-free languages in terms of recognizing devices. After that paper, these models have been almost forgotten for many years. Only recently limited automata were reconsidered in a series of papers, where several properties of them and of their variants have been investigated. In this work we present an overview of the most important results obtained in these researches. We also discuss some related models and possible lines for future investigations.
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Notes
- 1.
Actually, the original definition of d-limited automata was given by Hibbard by considering some kinds of rewriting systems [9]. It is not difficult to reformulate it, as we did, in terms of Turing machines.
- 2.
We could have moves that do not change the contents of a cell even in the first visit, as we seen in the above example of 1-limited automaton accepting \(K_n\). For a such a move, we can imagine that the cell is rewritten by the same symbol which is already in it.
- 3.
- 4.
The maximum number of visits to a cell up to the last rewriting, namely the measure corresponding to limited automata, is sometimes called dual return complexity [34].
- 5.
A nonunary rewriting alphabet is necessary for strongly limited automata to recognize all context-free languages. For instance, to recognize the set of palindromes, a working alphabet of at least 3 symbols is required [27].
References
Alur, R., Madhusudan, P.: Adding nesting structure to words. J. ACM 56(3), 16:1–16:43 (2009). https://doi.org/10.1145/1516512.1516518
Chomsky, N., Schützenberger, M.: The algebraic theory of context-free languages. In: Braffort, P., Hirschberg, D. (eds.) Computer Programming and Formal Systems, Studies in Logic and the Foundations of Mathematics, vol. 35, pp. 118–161. Elsevier (1963). https://doi.org/10.1016/S0049-237X(08)72023-8
Chrobak, M.: Finite automata and unary languages. Theoret. Comput. Sci. 47(3), 149–158 (1986). https://doi.org/10.1016/0304-3975(86)90142-8. Errata: 302(1–3), 497–498 (2003)
Ginsburg, S., Rice, H.G.: Two families of languages related to ALGOL. J. ACM 9(3), 350–371 (1962). https://doi.org/10.1145/321127.321132
Guillon, B., Pighizzini, G., Prigioniero, L., Průša, D.: Two-way automata and one-tape machines. In: Hoshi, M., Seki, S. (eds.) DLT 2018. LNCS, vol. 11088, pp. 366–378. Springer, Cham (2018). https://doi.org/10.1007/978-3-319-98654-8_30
Guillon, B., Prigioniero, L.: Linear-time limited automata. Theoret. Comput. Sci. (2019, in press). https://doi.org/10.1016/j.tcs.2019.03.037
Hemaspaandra, L.A., Mukherji, P., Tantau, T.: Context-free languages can be accepted with absolutely no space overhead. Inform. Comput. 203(2), 163–180 (2005). https://doi.org/10.1016/j.ic.2005.05.005
Hennie, F.C.: One-tape, off-line Turing machine computations. Inf. Control 8(6), 553–578 (1965)
Hibbard, T.N.: A generalization of context-free determinism. Inf. Control 11(1/2), 196–238 (1967)
Jančar, P., Mráz, F., Plátek, M.: Characterization of context-free languages by erasing automata. In: Havel, I.M., Koubek, V. (eds.) MFCS 1992. LNCS, vol. 629, pp. 307–314. Springer, Heidelberg (1992). https://doi.org/10.1007/3-540-55808-X_29
Jancar, P., Mráz, F., Plátek, M.: A taxonomy of forgetting automata. In: Borzyszkowski, A.M., Sokołowski, S. (eds.) MFCS 1993. LNCS, vol. 711, pp. 527–536. Springer, Heidelberg (1993). https://doi.org/10.1007/3-540-57182-5_44
Jančar, P., Mráz, F., Plátek, M.: Forgetting automata and context-free languages. Acta Inform. 33(5), 409–420 (1996). https://doi.org/10.1007/s002360050050
Jančar, P., Mráz, F., Plátek, M., Vogel, J.: Restarting automata. In: Reichel, H. (ed.) FCT 1995. LNCS, vol. 965, pp. 283–292. Springer, Heidelberg (1995). https://doi.org/10.1007/3-540-60249-6_60
Kutrib, M., Pighizzini, G., Wendlandt, M.: Descriptional complexity of limited automata. Inform. Comput. 259(2), 259–276 (2018). https://doi.org/10.1016/j.ic.2017.09.005
Kutrib, M., Wendlandt, M.: On simulation cost of unary limited automata. In: Shallit, J., Okhotin, A. (eds.) DCFS 2015. LNCS, vol. 9118, pp. 153–164. Springer, Cham (2015). https://doi.org/10.1007/978-3-319-19225-3_13
Kutrib, M., Wendlandt, M.: Reversible limited automata. Fund. Inform. 155(1–2), 31–58 (2017). https://doi.org/10.3233/FI-2017-1575
Mehlhorn, K.: Pebbling mountain ranges and its application to DCFL-recognition. In: de Bakker, J., van Leeuwen, J. (eds.) ICALP 1980. LNCS, vol. 85, pp. 422–435. Springer, Heidelberg (1980). https://doi.org/10.1007/3-540-10003-2_89
Nasyrov, I.R.: Deterministic realization of nondeterministic computations with a low measure of nondeterminism. Cybernetics 27(2), 170–179 (1991). https://doi.org/10.1007/BF01068368
Ogden, W.F., Ross, R.J., Winklmann, K.: An “interchange lemma” for context-free languages. SIAM J. Comput. 14(2), 410–415 (1985). https://doi.org/10.1137/0214031
Okhotin, A.: Non-erasing variants of the Chomsky–Schützenberger theorem. In: Yen, H.-C., Ibarra, O.H. (eds.) DLT 2012. LNCS, vol. 7410, pp. 121–129. Springer, Heidelberg (2012). https://doi.org/10.1007/978-3-642-31653-1_12
Otto, F.: Restarting automata and their relations to the Chomsky hierarchy. In: Ésik, Z., Fülöp, Z. (eds.) DLT 2003. LNCS, vol. 2710, pp. 55–74. Springer, Heidelberg (2003). https://doi.org/10.1007/3-540-45007-6_5
Peckel, J.: On a deterministic subclass of context-free languages. In: Gruska, J. (ed.) MFCS 1977. LNCS, vol. 53, pp. 430–434. Springer, Heidelberg (1977). https://doi.org/10.1007/3-540-08353-7_164
Peckel, J.: A deterministic subclass of context-free languages. Časopis pro pěstování matematiky 103(1), 43–52 (1978). http://eudml.org/doc/21335
Pighizzini, G.: Nondeterministic one-tape off-line Turing machines. J. Autom. Lang. Comb. 14(1), 107–124 (2009). https://doi.org/10.25596/jalc-2009-107. http://arXiv.org/abs/0905.1271
Pighizzini, G.: Two-way finite automata: old and recent results. Fund. Inform. 126(2–3), 225–246 (2013). https://doi.org/10.3233/FI-2013-879
Pighizzini, G.: Guest column: one-tape Turing machine variants and language recognition. SIGACT News 46(3), 37–55 (2015). https://doi.org/10.1145/2818936.2818947
Pighizzini, G.: Strongly limited automata. Fund. Inform. 148(3–4), 369–392 (2016). https://doi.org/10.3233/FI-2016-1439
Pighizzini, G., Pisoni, A.: Limited automata and regular languages. Internat. J. Found. Comput. Sci. 25(7), 897–916 (2014). https://doi.org/10.1142/S0129054114400140
Pighizzini, G., Pisoni, A.: Limited automata and context-free languages. Fund. Inform. 136(1–2), 157–176 (2015). https://doi.org/10.3233/FI-2015-1148
Pighizzini, G., Prigioniero, L.: Limited automata and unary languages. Inform. Comput. 266, 60–74 (2019). https://doi.org/10.1016/j.ic.2019.01.002
Sakoda, W.J., Sipser, M.: Nondeterminism and the size of two way finite automata. In: Lipton, R.J., Burkhard, W.A., Savitch, W.J., Friedman, E.P., Aho, A.V. (eds.) Proceedings 10th Annual ACM Symposium on Theory of Computing (STOC 1978), pp. 275–286. ACM (1978). https://doi.org/10.1145/800133.804357
Shepherdson, J.C.: The reduction of two-way automata to one-way automata. IBM J. Res. Dev. 3(2), 198–200 (1959). https://doi.org/10.1147/rd.32.0198
Sloane, N.J.A.: The on-line encyclopedia of integer sequences. http://oeis.org/A007814
Wagner, K.W., Wechsung, G.: Computational Complexity. D. Reidel Publishing Company, Dordrecht (1986)
Wechsung, G.: Characterization of some classes of context-free languages in terms of complexity classes. In: Bečvář, J. (ed.) MFCS 1975. LNCS, vol. 32, pp. 457–461. Springer, Heidelberg (1975). https://doi.org/10.1007/3-540-07389-2_233
Wechsung, G., Brandstädt, A.: A relation between space, return and dual return complexities. Theoret. Comput. Sci. 9, 127–140 (1979). https://doi.org/10.1016/0304-3975(79)90010-0
Yamakami, T.: Behavioral strengths and weaknesses of various models of limited automata. In: Catania, B., Královič, R., Nawrocki, J., Pighizzini, G. (eds.) SOFSEM 2019. LNCS, vol. 11376, pp. 519–530. Springer, Cham (2019). https://doi.org/10.1007/978-3-030-10801-4_40
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I am very grateful to Luca Prigioniero for his valuable and helpful comments.
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Pighizzini, G. (2019). Limited Automata: Properties, Complexity and Variants. In: Hospodár, M., Jirásková, G., Konstantinidis, S. (eds) Descriptional Complexity of Formal Systems. DCFS 2019. Lecture Notes in Computer Science(), vol 11612. Springer, Cham. https://doi.org/10.1007/978-3-030-23247-4_4
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