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Descriptional Complexity of Pushdown Store Languages [chapter]

Andreas Malcher, Katja Meckel, Carlo Mereghetti, Beatrice Palano
2012 Lecture Notes in Computer Science  
It is well known that the pushdown store language P (M ) of a pushdown automaton (PDA) M -i.e., the language consisting of words occurring on the pushdown along accepting computations of M -is a regular  ...  language.  ...  Finally, in Section 5, we apply our results on the descriptional complexity of pushdown store languages to the analysis of the hardness of some decision problems related to PDA.  ... 
doi:10.1007/978-3-642-31623-4_16 fatcat:5cyx4e42jrfijew6hfdw7ok7f4

Reversal-bounded multipushdown machines

Brenda S. Baker, Ronald V. Book
1974 Journal of computer and system sciences (Print)  
The first states that every r.e. set is the homomorphic image of the intersection of two linear context-free languages.  ...  The second states that every r.e. set is accepted by an on-line Turing acceptor with two pushdown stores such that in every computation, each pushdown store can make at most one reversal (that is, one  ...  ., s, let m i be the maximum of the lengths of the contents of the k pushdown stores at step i.  ... 
doi:10.1016/s0022-0000(74)80027-9 fatcat:4xbxafatyngnrlj63adkarkqpm

Removing Nondeterminism in Constant Height Pushdown Automata [chapter]

Zuzana Bednárová, Viliam Geffert, Carlo Mereghetti, Beatrice Palano
2012 Lecture Notes in Computer Science  
We study the descriptional cost of removing nondeterminism in constant height pushdown automata -i.e., pushdown automata with a built-in constant limit on the height of the pushdown.  ...  As a direct consequence, we get that eliminating nondeterminism in classical finite state automata is single-exponential even with the help of a constant height pushdown store.  ...  Acknowledgment The authors wish to thank the anonymous referee and the editors of Information and Computation for invaluable help.  ... 
doi:10.1007/978-3-642-31623-4_6 fatcat:5g7t466q3fdn7pegxegiplc4ma

Descriptional complexity of unambiguous input-driven pushdown automata

Alexander Okhotin, Kai Salomaa
2015 Theoretical Computer Science  
In addition, the methods developed in this paper are used to demonstrate that the descriptional complexity of complementation for nondeterministic IDPDAs is 2 Θ(n 2 ) , and that the descriptional complexity  ...  of homomorphisms for deterministic IDPDAs is 2 Θ(n 2 ) as well.  ...  Since the languages recognized by input-driven pushdown automata share many desirable properties of the regular languages, understanding the descriptional complexity trade-offs between the nondeterministic  ... 
doi:10.1016/j.tcs.2014.11.015 fatcat:rynx3o46i5dxrjswp3guycc6mu

Finite turns and the regular closure of linear context-free languages

Martin Kutrib, Andreas Malcher
2007 Discrete Applied Mathematics  
For example, automata with an unbounded number of turns that have to empty their pushdown store up to the initial symbol in order to start a new turn are characterized by the regular closure of the linear  ...  For both a bounded and an unbounded number of turns, requiring to empty the pushdown store is a strictly stronger condition than requiring to re-enter the initial state.  ...  This avoids that during the simulation the pushdown store gets empty, when M empties its pushdown store without accepting. It is easy to see that M accepts T (M) with empty pushdown store.  ... 
doi:10.1016/j.dam.2007.05.021 fatcat:fpkkcniuu5arvcddg5yc2ahg7y

A Direct Construction of Finite State Automata for Pushdown Store Languages [chapter]

Viliam Geffert, Andreas Malcher, Katja Meckel, Carlo Mereghetti, Beatrice Palano
2013 Lecture Notes in Computer Science  
Finally, we give a characterization of the class of pushdown store languages.  ...  We provide a new construction of a nondeterministic finite automaton (NFA) accepting the pushdown store language of a given pushdown automaton (PDA).  ...  Given a PDA M , its pushdown store language P (M ) consists of all words occurring on the pushdown store along accepting computation paths of M .  ... 
doi:10.1007/978-3-642-39310-5_10 fatcat:53fqmrikx5gdthih76ehitphz4

Some modifications of auxiliary pushdown automata

G. Buntrock, F. Drewes, C. Lautemann, T. Mossakowski
1991 RAIRO - Theoretical Informatics and Applications  
ACKNOWLEDGEMENTS We thank Birgit Jenner and Bernd Kirsig for pointing out to us and discussing with us the notions of "begin" and "end" nondeterminism.  ...  However, with the définitions given in this paper, restrictions in access to input and to pushdown store are clearly separated, and consequently, we find a more uniform spectrum of complexity classes and  ...  DISCUSSION In order to study the effect of adding both nondeterminism and an unlimited pushdown store to space bounded Turing machines, we have defined intermediate models in which pushdown store and/or  ... 
doi:10.1051/ita/1991250605451 fatcat:2uueqe4bivc6xenujsak6yjnlq

Page 1016 of Mathematical Reviews Vol. 52, Issue 3 [page]

1976 Mathematical Reviews  
A description of the relationship between the size of the time bound on a deterministic multitape Turing machine and the number and size of the counters used in a simulating two-way pushdown automaton  ...  Cook described a general relationship between L(n)-tape-bounded multitape Turing machines with an additional unbounded push- down store (called L(n)-tape-bounded auxiliary pushdown autom- ata) and 2°”-  ... 

Pushdown Control-Flow Analysis of Higher-Order Programs [article]

Christopher Earl, Matthew Might, David Van Horn
2010 arXiv   pre-print
One instantiation of this framework marks the first polyvariant pushdown analysis of higher-order programs; another marks the first polynomial-time analysis.  ...  To this young body of work on context-free analysis of higher-order programs, we contribute a pushdown control-flow analysis framework, which we derive as an abstract interpretation of a CESK machine with  ...  Acknowledgements We thank Dimitrios Vardoulakis for comments and discussions, and reviewers of ICFP and this workshop.  ... 
arXiv:1007.4268v1 fatcat:7lhbwmzqqfahhezs755ai4pvti

The time and tape complexity of developmental languages [chapter]

I. H. Sudborough
1977 Lecture Notes in Computer Science  
are EDTOL languages [21], and the existence of a linear context-free language which is log-tape complete for NSPACE (log n) [15].  ...  Furthermore, it is shown that all EOL languages are log-tape reducible to context-free languages. Hence, EOL ~ DSPACE (log n) if and only if every context-free language is in DSPACE (log n).  ...  Acknowledsements I am indebted to Jan Van Leeuwen for carefully reading an earlier version of this paper and his comments which helped improve the presentation.  ... 
doi:10.1007/3-540-08342-1_40 fatcat:dzoctnvjajfbdjtxu6x6xcgknq

Time and tape complexity of pushdown automaton languages

A.V. Aho, J.E. Hopcroft, J.D. Ullman
1968 Information and Control  
The use of pushdown stores is an important technique in the construction of compilers and other language processing devices.  ...  The 2D PDA languages are contained within the class of languages of time complexity n 2 log n. These results complement the results on one-way pushdown automata.  ... 
doi:10.1016/s0019-9958(68)91087-5 fatcat:fl35z4epi5em5owsp42cihl5ci

Descriptional Complexity of Two-Way Pushdown Automata with Restricted Head Reversals [chapter]

Andreas Malcher, Carlo Mereghetti, Beatrice Palano
2011 Lecture Notes in Computer Science  
In this paper, the subclass of 2PDA accepting bounded languages and making at most a constant number of input head turns is studied with respect to descriptional complexity aspects.  ...  If the restriction on boundedness of the languages considered and on the finiteness of the number of head and pushdown turns is dropped, the resulting trade-offs are no longer bounded by recursive functions  ...  Let D 1 be a descriptional system with complexity measure c 1 and D 2 be a descriptional system with complexity measure c 2 .  ... 
doi:10.1007/978-3-642-22600-7_20 fatcat:uqtdvvdeuvfihdwislhf424vly

Descriptional complexity of two-way pushdown automata with restricted head reversals

Andreas Malcher, Carlo Mereghetti, Beatrice Palano
2012 Theoretical Computer Science  
In this paper, the subclass of 2PDA accepting bounded languages and making at most a constant number of input head turns is studied with respect to descriptional complexity aspects.  ...  If the restriction on boundedness of the languages considered and on the finiteness of the number of head and pushdown turns is dropped, the resulting trade-offs are no longer bounded by recursive functions  ...  Let D 1 be a descriptional system with complexity measure c 1 and D 2 be a descriptional system with complexity measure c 2 .  ... 
doi:10.1016/j.tcs.2012.04.007 fatcat:cfomcx33jzd5ppxar4gkaxjziq

A New Approach to Formal Language Theory by Kolmogorov Complexity [article]

Ming Li and Paul Vitanyi (CWI and University of Amsterdam)
2001 arXiv   pre-print
We present a new approach to formal language theory using Kolmogorov complexity.  ...  The approach is also successful at the high end of the Chomsky hierarchy since one can quantify nonrecursiveness in terms of Kolmogorov complexity. (This is a preliminary uncorrected version.  ...  John Tromp improved the proof of Claim 1.  ... 
arXiv:cs/0110040v1 fatcat:qpcm5npokjb6pewwvfxguc7go4

Simulating two pushdown stores by one tape in 0(n1.5√log n) time

Ming Li
1988 Journal of computer and system sciences (Print)  
M' keeps a description of M in its finite control.  ...  In [BG], Book and Greibach proved that a three pushdown store or a one pushdown store and one stack nondeterministic machine can accept languages in Q + in real time. where Q+ is the set of languages accepted  ... 
doi:10.1016/0022-0000(88)90047-5 fatcat:j3yrnjafundl3cuyimu5bznuha
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