Hard Counting Problems for Partial Words

  • Florin Manea
  • Cătălin Tiseanu
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6031)


In this paper we approach several decision and counting problems related to partial words, from a computational point of view. First we show that finding a full word that is not compatible with any word from a given list of partial words, all having the same length, is NP-complete; from this we derive that counting the number of words that are compatible with at least one word from a given list of partial words, all having the same length, is #P-complete. We continue by showing that some other related problems are also #P-complete; from these we mention here only two: counting all the distinct full words of a given length compatible with at least one factor of the given partial word, and counting all the distinct squares compatible with at least a factor of a given partial word.


Partial Words NP-completeness #P Complexity Class #P-complete Problems Combinatorics on Words 


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© Springer-Verlag Berlin Heidelberg 2010

Authors and Affiliations

  • Florin Manea
    • 1
    • 2
  • Cătălin Tiseanu
    • 1
  1. 1.Faculty of Mathematics and Computer ScienceUniversity of BucharestBucharestRomania
  2. 2.Faculty of Computer ScienceOtto-von-Guericke-University Magdeburg, PSF 4120MagdeburgGermany

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