Optimal parallel computations for halin graphs

  • Krzysztof Diks
  • Wojciech Rytter
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 401)


Optimal parallel algorithms are given for two hard problems (the Hamiltonian cycle and the travelling salesman problem) restricted to graphs having a simple structure — Halin graphs. These problems were previously investigated for Halin graphs from the sequential point of view [1,5,6]. The travelling salesman problem (the computation of the shortest Hamiltonian cycle) for the Halin graph is interesting because such a graph can contain an exponential number of Hamiltonian cycles. Two tree-oriented algorithmic techniques are used: computation of products for paths of the tree (which gives log2n time algorithm for the Hamiltonian cycle) and a special parallel pebble game (giving log2n time for the travelling salesman problem).


Function dePe Travel Salesman Problem Hamiltonian Cycle Planar Embedding Parallel Random Access Machine 
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Copyright information

© Springer-Verlag Berlin Heidelberg 1989

Authors and Affiliations

  • Krzysztof Diks
    • 1
  • Wojciech Rytter
    • 1
  1. 1.Instytut InformatykiUniwersytet WarszawskiWarszawaPoland

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