The Snow Team Problem

(Clearing Directed Subgraphs by Mobile Agents)
  • Dariusz Dereniowski
  • Andrzej Lingas
  • Mia Persson
  • Dorota Urbańska
  • Paweł ŻylińskiEmail author
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 10472)


We study several problems of clearing subgraphs by mobile agents in digraphs. The agents can move only along directed walks of a digraph and, depending on the variant, their initial positions may be pre-specified. In general, for a given subset \(\mathcal {S}\) of vertices of a digraph D and a positive integer k, the objective is to determine whether there is a subgraph \(H=(\mathcal {V}_H,\mathcal {A}_H)\) of D such that (a) \(\mathcal {S}\subseteq \mathcal {V}_H\), (b) H is the union of k directed walks in D, and (c) the underlying graph of H includes a Steiner tree for \(\mathcal {S}\). We provide several results on parameterized complexity and hardness of the problems.


Graph searching FPT-algorithm NP-hardness Monomial 


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Copyright information

© Springer-Verlag GmbH Germany 2017

Authors and Affiliations

  • Dariusz Dereniowski
    • 1
  • Andrzej Lingas
    • 2
  • Mia Persson
    • 3
  • Dorota Urbańska
    • 1
  • Paweł Żyliński
    • 4
    Email author
  1. 1.Faculty of Electronics, Telecommunications and InformaticsGdańsk University of TechnologyGdańskPoland
  2. 2.Department of Computer ScienceLund UniversityLundSweden
  3. 3.Department of Computer ScienceMalmö UniversityMalmöSweden
  4. 4.Institute of InformaticsUniversity of GdańskGdańskPoland

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