At the time of his death this work was almost completed. We test whether a given solution of a quadratic 0-1 problem is optimal. The paper presents an algorithm based on the necessary and sufficient optimality condition introduced by Hirriart-Urruty for general convex problems. A measure of the quality of the solution is provided.
Computational results show the applicability of the method.
This work has been supported by Progetto Finalizzato Trasporti 2, Italian National Research Council, grant no.