A partially persistent data structure for the set-union problem with backtracking

  • Carlo Gaibisso
Chapter 3 Algorithmics
Part of the Lecture Notes in Computer Science book series (LNCS, volume 381)


An extension of the well known Set-Union problem is considered, where searching in the history of the partition and backtracking over the Union operations are possible. A partially persistent data structure is presented which maintains a partitions of an n-item set and performs each Union, each Find and each search in the past in O(lg n) time per operation, at the same time allowing to backtrack, over the sequence of Unions in costant time. The space complexity of such a structure is O(n).


Space Complexity Union Operation Array Access Space Complexity Analysis Void Link 
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 1989

Authors and Affiliations

  • Carlo Gaibisso
    • 1
  1. 1.Istituto di Analisi dei Sistemi ed Informatica del CNRRomeItaly

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