Finding triconnected components by local replacements

Extended abstract
  • Donald Fussell
  • Vijaya Ramachandran
  • Ramakrishna Thurimella
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 372)


We present an almost-optimal parallel algorithm for finding triconnected components on a CRCW PRAM. The time complexity of our algorithm is O(log n) and the processor-time product is O((m + n)·α(m, n)) where α is the inverse Ackerman function; here n is the number of vertices, and m is the number of edges in the graph. The algorithm is optimal for m≥n log* n. Our algorithm, like other parallel algorithms for this problem, is based on ear decomposition but it employs a new technique, local replacement, to improve the complexity. Only the need to find connected components, for which no optimal parallel algorithm that runs in O(log n) time is known, prevents our algorithm from achieving optimality on an EREW PRAM.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1989

Authors and Affiliations

  • Donald Fussell
    • 1
  • Vijaya Ramachandran
    • 1
  • Ramakrishna Thurimella
    • 1
  1. 1.Department of Computer SciencesUniversity of Texas at AustinAustin

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