O(1) parallel time incremental graph algorithms

  • Deepak D. Sherlekar
  • Shaunak Pawagi
  • I. V. Ramakrishnan
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 206)


Fast parallel algorithms are presented for updating minimum spanning trees, connected components and bridges of an undirected graph when a minor change is made to the graph such as addition or deletion of a vertex or an edge. The machine model used is a parallel random access machine that allows simultaneous reads as well as simultaneous writes into the same memory location. In the latter case one processor succeeds but we do not know which. The algorithms described in this paper require O(1) time and are efficient when compared to previously known O(logn) time algorithms for initial computation of the above mentioned graph properties on this model. An important feature of our algorithms is their versatility, that is, they can be adapted to run efficiently on all variations of this model with very little modification.


Span Tree Minimum Span Tree Cycle Basis Incremental Algorithm Tree Edge 


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Copyright information

© Springer-Verlag Berlin Heidelberg 1985

Authors and Affiliations

  • Deepak D. Sherlekar
    • 1
  • Shaunak Pawagi
    • 1
  • I. V. Ramakrishnan
    • 1
  1. 1.Department of Computer SclenceUniversity of MarylandCollege Park

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