On the Monotonicity of Weak Searching

  • Boting Yang
  • Yi Cao
Part of the Lecture Notes in Computer Science book series (LNCS, volume 5092)


In this paper, we propose and study two digraph searching models: weak searching and mixed weak searching. In these two searching models, each searcher must follow the edge directions when they move along edges, but the intruder can move from tail to head or from head to tail along edges. We prove the monotonicity of the mixed weak searching model by using Bienstock and Seymour’s method, and prove the monotonicity of the weak searching model by using LaPaugh’s method. We show that both searching problems are NP-complete.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2008

Authors and Affiliations

  • Boting Yang
    • 1
  • Yi Cao
    • 1
  1. 1.Department of Computer ScienceUniversity of Regina 

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