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An O(1) Time Algorithm for Generating Multiset Permutations

  • Tadao Takaoka
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1741)

Abstract

We design an algorithm that generates multiset permutati- ons in O(1) time from permutation to permutations, using only data structures of arrays. The previous O(1) time algorithm used pointers, causing O(n) time to access an element in a permutation, where n is the size of permutations. The central idea in our algorithm is tree traversal. We associate permutations with the leaves of a tree. By traversing this tree, going up and down and making changes when necessary, we spend O(1) time from permutation to permutation. Permutations are generated in a one-dimensional array.

Keywords

Time Algorithm Recursive Algorithm Solution Point Opposite Path Landing Point 
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 1999

Authors and Affiliations

  • Tadao Takaoka
    • 1
  1. 1.Department of Computer ScienceUniversity of CanterburyChristchurchNew Zealand

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