Ambiguity in omega context free languages

نویسنده

  • Olivier Finkel
چکیده

We extend the well-known notions of ambiguity and of degrees of ambiguity of 0nitary context free languages to the case of omega context free languages (!-CFL) accepted by B3 uchi or Muller pushdown automata. We show that these notions may be de0ned independently of the B3 uchi or Muller acceptance condition which is considered. We investigate 0rst properties of the subclasses of omega context free languages we get in that way, giving many examples and studying topological properties of !-CFL of a given degree of ambiguity. c © 2002 Elsevier Science B.V. All rights reserved.

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عنوان ژورنال:
  • Theor. Comput. Sci.

دوره 1-3  شماره 

صفحات  -

تاریخ انتشار 2003