Bounding Clique-Width via Perfect Graphs
نویسندگان
چکیده
Given two graphs H1 and H2, a graph G is (H1,H2)-free if it contains no subgraph isomorphic to H1 or H2. We continue a recent study into the clique-width of (H1,H2)-free graphs and present three new classes of (H1, H2)-free graphs that have bounded clique-width. We also show the implications of our results for the computational complexity of the Colouring problem restricted to (H1,H2)-free graphs. The three new graph classes have in common that one of their two forbidden induced subgraphs is the diamond (the graph obtained from a clique on four vertices by deleting one edge). To prove boundedness of their cliquewidth we develop a technique that is based on bounding clique covering number in combination with reduction to subclasses of perfect graphs.
منابع مشابه
Bounding the Clique-Width of H-free Chordal Graphs
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