Twin-Cover: Beyond Vertex Cover in Parameterized Algorithmics

  • Robert Ganian
Part of the Lecture Notes in Computer Science book series (LNCS, volume 7112)


Parameterized algorithms are a very useful tool for dealing with NP-hard problems on graphs. In this context, vertex cover is used as a powerful parameter for dealing with problems which are hard to solve even on graphs of bounded tree-width. The drawback of vertex cover is that bounding it severely restricts admissible graph classes. We introduce a new parameter called twin-cover and show that it is capable of solving a wide range of hard problems while also being much less restrictive than vertex cover and attaining low values even on dense graphs.

The article begins by introducing a new FPT algorithm for Graph Motif on graphs of bounded vertex cover. This is the first algorithm of this kind for Graph Motif. We continue by defining twin-cover and providing some related results and notions. The next section contains a number of new FPT algorithms on graphs of bounded twin-cover, with a special emphasis on solving problems which are hard even on graphs of bounded tree-width. Finally, section five generalizes the recent results of Michael Lampis for \(M\!S_1\) model checking from vertex cover to twin-cover.


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© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  • Robert Ganian
    • 1
  1. 1.Faculty of InformaticsMasaryk UniversityBrnoCzech Republic

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