Hierarchies of One-Way Multihead Automata Languages

Abstract Let DPDA( k ) (respectively NPDA( k )) be the class of languages recognized by one-way k -head deterministic (respectively nondeterministic) pushdown automata. The main result of this paper is that, for every k>0, DPDA (k) ⊊ DPDA (k+1) and DPDA (k) ⊊ NPDA (k) .

[1]  Seymour Ginsburg,et al.  The mathematical theory of context free languages , 1966 .

[2]  Oscar H. Ibarra,et al.  A Note on Semilinear Sets and Bounded-Reversal Multihead Pushdown Automata , 1974, Inf. Process. Lett..

[3]  Marek Chrobak.  Variations on the Technique of Duris and Galil , 1985, J. Comput. Syst. Sci..

[4]  I. HAL SUDBOROUGH.  One-Way Multihead Writing Finite Automata , 1976, Inf. Control..

[5]  Sheila A. Greibach,et al.  An Infinite Hierarchy of Context-Free Languages , 1969, JACM.

[6]  Andrew Chi-Chih Yao,et al.  K + 1 heads are better than K , 1976, 17th Annual Symposium on Foundations of Computer Science (sfcs 1976).

[7]  Burkhard Monien.  Transformational methods and their application to complexity problems , 1976, Acta Informatica.

[8]  Richard E. Ladner,et al.  Space Bounds for Processing Contentless Inputs , 1975, J. Comput. Syst. Sci..

[9]  Wolfgang J. Paul,et al.  On-line simulation of k+1 tapes by k tapes requires nonlinear time , 1982, 23rd Annual Symposium on Foundations of Computer Science (sfcs 1982).

[10]  Ivan Hal Sudborough,et al.  Some Remarks on Multihead Automata , 1977, RAIRO Theor. Informatics Appl..

[11]  Joel I. Seiferas.  Techniques for Separating Space Complexity Classes , 1977, J. Comput. Syst. Sci..

[12]  S. Ginsburg,et al.  BOUNDED ALGOL-LIKE LANGUAGES^) , 1964 .

[13]  Oscar H. Ibarra,et al.  Two-Way Pushdown Automata , 1967, Inf. Control..

[14]  Burkhard Monien.  Two-Way Multihead Automata Over a One-Letter Alphabet , 1980, RAIRO Theor. Informatics Appl..

[15]  Satoru Miyano,et al.  Remarks on Multihead Pushdown Automata and Multihead Stack Automata , 1983, J. Comput. Syst. Sci..

[16]  Ming Li,et al.  Lower Bounds by Kolmogorov-Complexity (Extended Abstract) , 1985, ICALP.

[17]  Stephen A. Cook,et al.  Characterizations of Pushdown Machines in Terms of Time-Bounded Computers , 1971, J. ACM.

[18]  Juris Hartmanis,et al.  On Tape Bounds for Single Letter Alphabet Language Processing , 1976, Theor. Comput. Sci..

[19]  Serafino Amoroso,et al.  Maps Preserving the Uniformity of Neighborhood Interconnection Patterns in Tessellation Structures , 1974, Inf. Control..

[20]  Oscar H. Ibarra,et al.  On Two-way Multihead Automata , 1973, J. Comput. Syst. Sci..

[21]  Jeffrey D. Ullman,et al.  Introduction to Automata Theory, Languages and Computation , 1979 .

[22]  Juraj Hromkovic,et al.  One-Way Simple Multihead Finite Automata are not Closed Under Concatenation , 1983, Theor. Comput. Sci..

[23]  Oscar H. Ibarra,et al.  Multi-Tape and Multi-Head Pushdown Automata , 1968, Inf. Control..

[24]  Burkhard Monien,et al.  Transformational methods and their application to complexity problems , 1976, Acta Informatica.

[25]  Thomas Frank. Piatkowski.  n-head finite state machines , 1963 .

[26]  Seymour Ginsburg,et al.  BOUNDED REGULAR SETS , 1966 .

[27]  Zvi Galil,et al.  Fooling a two Way Automaton or one Pushdown Store is better than one Counter for two Way Machines , 1982, Theor. Comput. Sci..

[28]  Oscar H. Ibarra,et al.  Characterizations of Some Tape and Time Complexity Classes of Turing Machines in Terms of Multihead and Auxiliary Stack Automata , 1971, J. Comput. Syst. Sci..

[29]  Ivan Hal Sudborough,et al.  THE INTERFACE BETWEEN LANGUAGE THEORY AND COMPLEXITY THEORY , 1980 .

[30]  Oscar H. Ibarra,et al.  A Useful Device for Showing the Solvability of Some Decision Problems , 1976, J. Comput. Syst. Sci..

[31]  Joel I. Seiferas,et al.  Relating Refined Space Complexity Classes , 1977, J. Comput. Syst. Sci..

[32]  S. Ginsburg,et al.  Bounded -like languages , 1964 .

[33]  Juraj Hromkovic.  Closure Properties of the Family of Languages Recognized by One-Way Two-Head Deterministic Finite State Automata , 1981, MFCS.

[34]  Katsushi Inoue,et al.  One-Way Simple Multihead Finite Automata , 1979, Theor. Comput. Sci..

[35]  F. C. Hennie,et al.  One-Tape, Off-Line Turing Machine Computations , 1965, Inf. Control..

[36]  Endre Szemerédi,et al.  On determinism versus non-determinism and related problems , 1983, 24th Annual Symposium on Foundations of Computer Science (sfcs 1983).