Alogtime algorithms for tree isomorphism, comparison, and canonization

  • Samuel R. Buss
Invited Papers
First Online:
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1289)

Abstract

The tree isomorphism problem is the problem of determining whether two trees are isomorphic. The tree canonization problem is the problem of producing a canonical tree isomorphic to a given tree. The tree comparison problem is the problem of determining whether one tree is less than a second tree in a natural ordering on trees. We present alternating logarithmic time algorithms for the tree isomorphism problem, the tree canonization problem and the tree comparison problem. As a consequence, there is a recursive enumeration of the alternating log time tree problems.

Keywords

String Representation Parent Tree Tree Comparison Recursive Call Canonical Representation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
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Copyright information

© Springer-Verlag Berlin Heidelberg 1997

Authors and Affiliations

  • Samuel R. Buss
    • 1
  1. 1.Departments of Mathematics & Computer ScienceUniv. of California, San DiegoLa Jolla

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