Directed Searching Digraphs: Monotonicity and Complexity

  • Boting Yang
  • Yi Cao
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4484)


In this paper, we introduce and study two new search models on digraphs: the directed searching and mixed directed searching. In these two search models, both searchers and intruders must follow the edge directions when they move along edges. We prove the monotonicity of both search models, and we show that both directed and mixed directed search problems are NP-complete.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2007

Authors and Affiliations

  • Boting Yang
    • 1
  • Yi Cao
    • 2
  1. 1.Department of Computer Science, University of Regina 
  2. 2.Department of Computing Science, University of Alberta 

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