Abstract
We present the technique of local recompression on the example of word equations. The technique is based on local modification of variables (replacing X by aX or Xa) and replacement of pairs of letters appearing in the equation by a ‘fresh’ letter, which can be seen as a bottom-up building of an SLP (Straight-Line Programme) for the solution of the word equation, i.e. a compression.
Using this technique we give a simple proof that satisfiability of word equations is in PSPACE. Furthermore we sketch the applications for some problems regarding the SLP compressed strings.
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Jeż, A. (2013). Recompression: Word Equations and Beyond. In: Béal, MP., Carton, O. (eds) Developments in Language Theory. DLT 2013. Lecture Notes in Computer Science, vol 7907. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-38771-5_2
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DOI: https://doi.org/10.1007/978-3-642-38771-5_2
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