Two-Way Transducers with a Two-Way Output Tape

  • Olivier Carton
Part of the Lecture Notes in Computer Science book series (LNCS, volume 7410)


In this paper, we consider two-way transducers with a two-way output tape. To each cell of the input tape corresponds a cell of the output tape where the transducer can write a finite word. At each transition, the transducer reads one cell of the input tape and either leave unchanged the corresponding cell of the output tape or write a new word into it, overwriting the previous content. We show that each relation realized by such a two-way transducer is rational. It can be realized by a one-way transducer. We also show that any rational function can be realized by a deterministic two-way transducer.


Rational Function Expressive Power Empty Word Input Word Input Tape 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  • Olivier Carton
    • 1
  1. 1.LIAFAUniversité Paris Diderot & CNRSFrance

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