Graph Coloring via Constraint Programming-based Column Generation
نویسندگان
چکیده
This paper presents a Constraint Programming-based Column Generation approach to the Minimum Graph Coloring problem. The proposed approach has two versions of the pricing subproblems: the first version formulates the pricing subproblem as the optimization problem of finding the most negative reduced cost column, the second version as the decision problem of finding a maximal stable set with negative reduced cost smaller than a given threshold. The value of the thresholds is not fixed a priori, but is computed during the execution of the column generation. Additionally, we introduce a so-called Constraint Programming augmented pricing with the aim of generating integer feasible solutions during the execution of the column generation algorithm. The proposed CP-based Column Generation results in a very efficient exact method for the minimum graph coloring coloring, being able to solve many hard instances of the DIMACS coloring benchmarks.
منابع مشابه
Exact Solution of Graph Coloring Problems via Constraint Programming and Column Generation
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