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Title: From Cliques to Colorings and Back Again
We present an exact algorithm for graph coloring and maximum clique problems based on SAT technology. It relies on four sub-algorithms that alternatingly compute cliques of larger size and colorings with fewer colors. We show how these techniques can mutually help each other: larger cliques facilitate finding smaller colorings, which in turn can boost finding larger cliques. We evaluate our approach on the DIMACS graph coloring suite. For finding maximum cliques, we show that our algorithm can improve the state-of-the-art MaxSAT-based solver IncMaxCLQ, and for the graph coloring problem, we close two open instances, decrease two upper bounds, and increase one lower bound.  more » « less
Award ID(s):
1918102 2006363
NSF-PAR ID:
10357179
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
28th International Conference on Principles and Practice of Constraint Programming (CP 2022)
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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