The computational complexity of the role assignment problem
ICALP'03 Proceedings of the 30th international conference on Automata, languages and programming
Computing role assignments of chordal graphs
FCT'09 Proceedings of the 17th international conference on Fundamentals of computation theory
Distance constrained labelings of trees
TAMC'08 Proceedings of the 5th international conference on Theory and applications of models of computation
Comparing universal covers in polynomial time
CSR'08 Proceedings of the 3rd international conference on Computer science: theory and applications
Computing role assignments of chordal graphs
Theoretical Computer Science
Complexity of locally injective homomorphism to the theta graphs
IWOCA'10 Proceedings of the 21st international conference on Combinatorial algorithms
Locally injective homomorphism to the simple weight graphs
TAMC'11 Proceedings of the 8th annual conference on Theory and applications of models of computation
Locally injective graph homomorphism: lists guarantee dichotomy
WG'06 Proceedings of the 32nd international conference on Graph-Theoretic Concepts in Computer Science
Distance constrained labelings of graphs of bounded treewidth
ICALP'05 Proceedings of the 32nd international conference on Automata, Languages and Programming
Matrix and graph orders derived from locally constrained graph homomorphisms
MFCS'05 Proceedings of the 30th international conference on Mathematical Foundations of Computer Science
Locally constrained graph homomorphisms-structure, complexity, and applications
Computer Science Review
Exact algorithms for L(2, 1)-labeling of graphs
MFCS'07 Proceedings of the 32nd international conference on Mathematical Foundations of Computer Science
Exact algorithm for graph homomorphism and locally injective graph homomorphism
Information Processing Letters
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A graph G partially covers a graph H if it allows a locally injective homomorphism from G to H, i.e. an edge-preserving vertex mapping which is injective on the closed neighborhood of each vertex of G. The notion of partial covers is closely related to the generalized frequency assignment problem. We study the computational complexity of the question whether an input graph G partially covers a fixed graph H. Since this problem is at least as difficult as deciding the existence of a full covering projection (a locally bijective homomorphism), we concentrate on classes of problems (described by parameter graphs H) for which the full cover problem is polynomially solvable. In particular, we treat graphs H which contain at most two vertices of degree greater than two, and for such graphs we exhibit both NP-complete and polynomially solvable instances. The techniques are based on newly introduced notions of generalized matchings and edge precoloring extension of bipartite graphs.