Complexity Results on Register Context-Free Grammars and Register Tree Automata

  • Ryoma SendaEmail author
  • Yoshiaki Takata
  • Hiroyuki Seki
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 11187)


Register context-free grammars (RCFG) and register tree automata (RTA) are an extension of context-free grammars and tree automata, respectively, to handle data values in a restricted way. RTA are paid attention as a model of query languages for structured documents such as XML with data values. This paper investigates the computational complexity of the basic decision problems for RCFG and RTA. We show that the membership and emptiness problems for RCFG are EXPTIME-complete and also show how the complexity reduces by introducing subclasses of RCFG. The complexity of these problems for RTA are also shown to be NP-complete and EXPTIME-complete.



This work was supported by JSPS KAKENHI Grant Number JP15H02684.


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Authors and Affiliations

  1. 1.Graduate School of Information ScienceNagoya UniversityNagoyaJapan
  2. 2.Graduate School of EngineeringKochi University of TechnologyKami CityJapan

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