TY - GEN
T1 - Locally Constrained Homomorphisms on Graphs of Bounded Treewidth and Bounded Degree
AU - Chaplick, Steven
AU - Fiala, Jirí
AU - Hof, Pim van 't
AU - Paulusma, Daniël
AU - Tesar, Marek
N1 - DBLP's bibliographic metadata records provided through http://dblp.org/search/publ/api are distributed under a Creative Commons CC0 1.0 Universal Public Domain Dedication. Although the bibliographic metadata records are provided consistent with CC0 1.0 Dedication, the content described by the metadata records is not. Content may be subject to copyright, rights of privacy, rights of publicity and other restrictions.
PY - 2013
Y1 - 2013
N2 - A homomorphism from a graph g to a graph h is locally bijective, surjective, or injective if its restriction to the neighborhood of every vertex of g is bijective, surjective, or injective, respectively. We prove that the problems of testing whether a given graph g allows a homomorphism to a given graph h that is locally bijective, surjective, or injective, respectively, are np-complete, even when g has pathwidth at most 5, 4 or 2, respectively, or when both g and h have maximum degree 3. We complement these hardness results by showing that the three problems are polynomial-time solvable if g has bounded treewidth and in addition g or h has bounded maximum degree.keywordspolynomial timemaximum degreeconstraint satisfaction problemtree decompositionsurjective homomorphismthese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
AB - A homomorphism from a graph g to a graph h is locally bijective, surjective, or injective if its restriction to the neighborhood of every vertex of g is bijective, surjective, or injective, respectively. We prove that the problems of testing whether a given graph g allows a homomorphism to a given graph h that is locally bijective, surjective, or injective, respectively, are np-complete, even when g has pathwidth at most 5, 4 or 2, respectively, or when both g and h have maximum degree 3. We complement these hardness results by showing that the three problems are polynomial-time solvable if g has bounded treewidth and in addition g or h has bounded maximum degree.keywordspolynomial timemaximum degreeconstraint satisfaction problemtree decompositionsurjective homomorphismthese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
U2 - 10.1007/978-3-642-40164-0_14
DO - 10.1007/978-3-642-40164-0_14
M3 - Conference article in proceeding
T3 - Lecture Notes in Computer Science
SP - 121
EP - 132
BT - Fundamentals of Computation Theory. FCT 2013
PB - Springer, Berlin, Heidelberg
ER -