LIFO-Search on Digraphs: A Searching Game for Cycle-Rank

  • Paul Hunter
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6914)


We consider the extension of the last-in-first-out graph searching game of Giannopoulou and Thilikos to digraphs. We show that all common variations of the game require the same number of searchers, and the minimal number of searchers required is one more than the cycle-rank of the digraph. We also obtain a tight duality theorem, giving a precise min-max characterization of obstructions for cycle-rank.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2011

Authors and Affiliations

  • Paul Hunter
    • 1
  1. 1.Department of Computer ScienceUniversity of OxfordUK

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