On the equivalence of two-way pushdown automata and counter machines over bounded languages

  • Oscar H. Ibarra
  • Tao Jiang
  • Nicholas Tran
  • Hui Wang
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 665)


It is known that two-way pushdown automata ate more powerful than two-way counter machines. The result is also true for the case when the pushdown store and counter are reversal-bounded. In contrast, we show that two-way reversal-bounded pushdown automata over bounded languages (i.e., subsets of w 1 * ... w k * for some nonnull words w1 ..., wk) are equivalent to two-way reversal-bounded counter machines. We also show that, unlike the unbounded input case, two-way reversal-bounded pushdown automata over bounded languages have decidable emptiness, equivalence and containment problems.


Turn Point Counter Machine Pushdown Automaton Input Segment Finite Control 
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Copyright information

© Springer-Verlag Berlin Heidelberg 1993

Authors and Affiliations

  • Oscar H. Ibarra
    • 1
  • Tao Jiang
    • 2
  • Nicholas Tran
    • 1
  • Hui Wang
    • 3
  1. 1.Department of Computer ScienceUniversity of CaliforniaSanta Barbara
  2. 2.Department of Computer Science and SystemsMcMaster UniversityHamiltonCanada
  3. 3.Department of Computer ScienceUniversity of Alabama in Huntsville

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