• B-chromatic number: Beyond NP-hardness 

      Panolan, Fahad; Philip, Geevarghese; Saurabh, Saket (Peer reviewed; Journal article, 2015)
      The b-chromatic number of a graph G, chi_b(G), is the largest integer k such that G has a k-vertex coloring with the property that each color class has a vertex which is adjacent to at least one vertex in each of the other ...
    • Connecting Vertices by Independent Trees 

      Basavaraju, Manu; Fomin, Fedor; Golovach, Petr; Saurabh, Saket (Journal article; Peer reviewed, 2014)
      We study the paramereteized complexity of the following connectivity problem. For a vertex subset U of a graph G, trees T1, . . . , Ts of G are completely independent spanning trees of U if each of them contains U , and ...
    • Fast biclustering by dual parameterization 

      Drange, Pål Grønås; Reidl, Felix; Villaamil, Fernando Sánchez; Sikdar, Somnath (Peer reviewed; Journal article, 2015)
      We study two clustering problems, Starforest Editing, the problem of adding and deleting edges to obtain a disjoint union of stars, and the generalization Bicluster Editing. We show that, in addition to being NP-hard, none ...
    • Kernelization of Vertex Cover by Structural Parameters 

      Strømme, Torstein Jarl Fagerbakke (Master thesis, 2015-08-03)
      In the NP-complete problem Vertex Cover, one is given a graph G and an integer k and are asked whether there exists a vertex set S ⊆ V (G) with size at most k such that every edge of the graph is incident to a vertex in ...
    • On cutwidth parameterized by vertex cover 

      Cygan, Marek; Lokshtanov, Daniel; Pilipczuk, Marcin; Pilipczuk, Michal Pawel; Saurabh, Saket (Peer reviewed; Journal article, 2014-04)
      We study the CUTWIDTH problem, where the input is a graph G, and the objective is find a linear layout of the vertices that minimizes the maximum number of edges intersected by any vertical line inserted between two ...
    • Parameterized complexity of secluded connectivity problems 

      Fomin, Fedor; Golovach, Petr; Karpov, Nikolay; Kulikov, Alexander S (Peer reviewed; Journal article, 2015)
      The Secluded Path problem introduced by Chechik et al. in [ESA 2013] models a situation where a sensitive information has to be transmitted between a pair of nodes along a path in a network. The measure of the quality of ...
    • Subexponential Algorithms for Partial Cover Problems 

      Fomin, Fedor; Lokshtanov, Daniel; Raman, Venkatesh; Saurabh, Saket (Peer reviewed; Journal article, 2009)
      Partial Cover problems are optimization versions of fundamental and well studied problems like {\sc Vertex Cover} and {\sc Dominating Set}. Here one is interested in covering (or dominating) the maximum number of edges (or ...
    • Tight bounds for parameterized complexity of Cluster Editing 

      Fomin, Fedor; Kratsch, Stefan; Pilipczuk, Marcin; Pilipczuk, Michal Pawel; Villanger, Yngve (Peer reviewed; Journal article, 2013)
      In the Correlation Clustering problem, also known as Cluster Editing, we are given an undirected graph G and a positive integer k; the task is to decide whether G can be transformed into a cluster graph, i.e., a disjoint ...