Strong cliques in diamond-free graphs
نویسندگان
چکیده
A strong clique in a graph is intersecting all inclusion-maximal stable sets. Strong cliques play an important role the study of perfect graphs. We class diamond-free graphs, from both structural and algorithmic points view. show that following five NP -hard or co-NP problems remain when restricted to graphs: Is given strong? Does have clique? every vertex contained Given partition set into cliques, Can be partitioned cliques? On positive side, we three whose computational complexity open general can solved polynomial time induced subgraph maximal edge The last two results are derived characterization graphs which strong, also implies improved Erd?s-Hajnal property for such • characterize CIS their property. co-strongly derive hardness related problems.
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ژورنال
عنوان ژورنال: Theoretical Computer Science
سال: 2021
ISSN: ['1879-2294', '0304-3975']
DOI: https://doi.org/10.1016/j.tcs.2020.12.001