Summary
Let L b = {w 1 *...* w 2b ¦w i is in {0,1}* and w i = w 2b+1−i for 1≦i≦2b for b≧1. We show that the language L b is not recognizable by any nondeterministic one-way k-head stack-counter automata if \(b > \left( {\begin{array}{*{20}c} k \\ 2 \\ \end{array} } \right)\). As a corollary, we show that k+1 heads are better than k for one-way multihead stack-counter automata.
Similar content being viewed by others
References
Book, R.V., Ginsburg, S.: Multi-stack-counter languages. Math. Systems Theory 6, 37–48 (1972)
Ginsburg, S., Greibach, S.A., Harrison, M.A.: One-way stack automata. J. Assoc. Comput. Mach. 14, 389–418 (1967)
Ginsburg, S., Rose, G.F.: The equivalence of stack-counter acceptors and quasi-realtime stackcounter acceptors. J. Comput. System Sci. 8, 243–269 (1974)
Harrison, M.A., Ibarra, O.H.: Multi-tape amd multi-head pushdown automata. Inform. and Contr. 13, 433–470 (1968)
Ibarra, O.H., Kim, C.E.: On 3-head versus 2-head finite automata, Acta Informat. 4, 193–200 (1975)
Rosenberg, A.L.: On multihead finite automata. IBM J. Res. and Develop. 10, 388–394 (1966)
Sudborough, I.H.: One-way multihead writing finite automata. Inform. and Contr. 30, 1–20 (1976)
Yao, A.C., Rivest, R.L.: k+1 heads are better than k. J. Assoc. Comput. Mach. 25, 337–340 (1978)
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Miyano, S. A hierarchy theorem for multihead stack-counter automata. Acta Informatica 17, 63–67 (1982). https://doi.org/10.1007/BF00262976
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00262976