Fixed Parameter Algorithms for Counting and Deciding Bounded Restrictive List H-Colorings

(Extended Abstract)
  • Josep Díaz
  • Maria Serna
  • Dimitrios M. Thilikos
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3221)


We study the fixed parameter tractability of the parameterized counting and decision version of the restrictive H-coloring problem. These problems are defined by fixing the number of preimages of a subset C of the vertices in H through a partial weight assignment (H,C,K). We consider two families of partial weight assignment the simple and the plain. For simple partial weight assignments we show an FPT algorithm for counting list (H,C,K)-colorings and faster algorithms for its decision version. For the more general class of plain partial weight assignment we give an FPT algorithm for the (H,C,K)-coloring decision problem. We introduce the concept of compactor and an algorithmic technique, compactor enumeration, that allow us to design the FPT algorithms for the counting version (and probably export the technique to other problems).


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Copyright information

© Springer-Verlag Berlin Heidelberg 2004

Authors and Affiliations

  • Josep Díaz
    • 1
  • Maria Serna
    • 1
  • Dimitrios M. Thilikos
    • 1
  1. 1.Dept. de Llenguatges i Sistemes InformàticsUniversitat Politècnica de CatalunyaBarcelonaSpain

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