The Computational Complexity of the Role Assignment Problem
نویسندگان
چکیده
A graph G is R-role assignable if there is a locally surjective homomorphism from G to R, i.e. a vertex mapping r : VG → VR, such that the neighborhood relation is preserved: r(NG(u)) = NR(r(u)). Kristiansen and Telle conjectured that the decision problem whether such a mapping exists is an NP-complete problem for any connected graph R on at least three vertices. In this paper we prove the conjecture and show further corollaries for disconnected graphs and related problems.
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