English

Approximation for Maximum Surjective Constraint Satisfaction Problems

Computational Complexity 2011-10-14 v1

Abstract

Maximum surjective constraint satisfaction problems (Max-Sur-CSPs) are computational problems where we are given a set of variables denoting values from a finite domain B and a set of constraints on the variables. A solution to such a problem is a surjective mapping from the set of variables to B such that the number of satisfied constraints is maximized. We study the approximation performance that can be acccchieved by algorithms for these problems, mainly by investigating their relation with Max-CSPs (which are the corresponding problems without the surjectivity requirement). Our work gives a complexity dichotomy for Max-Sur-CSP(B) between PTAS and APX-complete, under the assumption that there is a complexity dichotomy for Max-CSP(B) between PO and APX-complete, which has already been proved on the Boolean domain and 3-element domains.

Keywords

Cite

@article{arxiv.1110.2953,
  title  = {Approximation for Maximum Surjective Constraint Satisfaction Problems},
  author = {Walter Bach and Hang Zhou},
  journal= {arXiv preprint arXiv:1110.2953},
  year   = {2011}
}
R2 v1 2026-06-21T19:19:46.286Z