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**Optimal Approximation Algorithms for Reoptimization of Constraint Satisfaction Problems** ()

The purpose of reoptimization using approximation methods—application
of knowledge about the solution of the initial instance *I*, provided to achieve a better quality of approximation (approximation ratio) of an
algorithm for determining optimal or close to it solutions of some “minor”
changes of instance *I*. To solve the problem *Ins-Max-EkCSP-P* (reoptimization of *Max-EkCSP-P* with the addition of
one constraint) with approximation resistant predicate *P* exists a polynomial threshold (optimal) -approximation
algorithm, where the
threshold “random” approximation ratio of *P*). When the
unique games conjecture (UGC) is hold there exists a polynomial threshold
(optimal) -approximation
algorithm (where and the
integrality gap of semidefinite relaxation of *Max-EkCSP-P* problem *Z*) to solve the problem *Ins-Max-EkCSP-P*.

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*American Journal of Operations Research*, Vol. 3 No. 2, 2013, pp. 279-288. doi: 10.4236/ajor.2013.32025.

Conflicts of Interest

The authors declare no conflicts of interest.

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