The Space Complexity of k-Tree Isomorphism

  • V. Arvind
  • Bireswar Das
  • Johannes Köbler
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4835)


We show that isomorphism testing of k-trees is in the class StUSPACE(logn) (strongly unambiguous logspace). This bound follows from a deterministic logspace algorithm that accesses a strongly unambiguous logspace oracle for canonizing k-trees. Further we give a logspace canonization algorithm for k-paths.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2007

Authors and Affiliations

  • V. Arvind
    • 1
  • Bireswar Das
    • 1
  • Johannes Köbler
    • 2
  1. 1.The Institute of Mathematical Sciences, Chennai 600 113India
  2. 2.Institut für Informatik, Humboldt Universität zu BerlinGermany

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