Unique decodability of bigram counts by finite automata

نویسندگان

  • Aryeh Kontorovich
  • Ari Trachtenberg
چکیده

We revisit the problem of deciding whether a given string is uniquely decodable from its bigram counts by means of a finite automaton. An efficient algorithm for constructing a polynomial-size nondeterministic finite automaton that decides unique decodability is given. Conversely, we show that the minimum deterministic finite automaton for deciding unique decodability has at least exponentially many states in alphabet size.

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عنوان ژورنال:
  • CoRR

دوره abs/1111.6431  شماره 

صفحات  -

تاریخ انتشار 2011