Graph Unique-Maximum and Conflict-Free Colorings

  • Panagiotis Cheilaris
  • Géza Tóth
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6078)


We investigate the relationship between two kinds of vertex colorings of graphs: unique-maximum colorings and conflict-free colorings. In a unique-maximum coloring, the colors are ordered, and in every path of the graph the maximum color appears only once. In a conflict-free coloring, in every path of the graph there is a color that appears only once. We also study computational complexity aspects of conflict-free colorings and prove a completeness result. Finally, we improve lower bounds for those chromatic numbers of the grid graph.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2010

Authors and Affiliations

  • Panagiotis Cheilaris
    • 1
  • Géza Tóth
    • 2
  1. 1.Center for Advanced Studies in MathematicsBen-Gurion UniversityIsrael
  2. 2.Rényi Institute, Hungarian Academy of SciencesHungary

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