The classification of coverings of processor networks
Journal of Parallel and Distributed Computing
The monadic second-order logic of graphs. I. recognizable sets of finite graphs
Information and Computation
Journal of Combinatorial Theory Series B
Graph classes: a survey
A Linear Time Algorithm for Deciding Interval Graph Isomorphism
Journal of the ACM (JACM)
Fixed parameter complexity of λ-labelings
Discrete Applied Mathematics - special issue on the 25th international workshop on graph theoretic concepts in computer science (WG'99)
Computers and Intractability: A Guide to the Theory of NP-Completeness
Computers and Intractability: A Guide to the Theory of NP-Completeness
Local and global properties in networks of processors (Extended Abstract)
STOC '80 Proceedings of the twelfth annual ACM symposium on Theory of computing
2-role assignments on triangulated graphs
Theoretical Computer Science
Algorithmic Graph Theory and Perfect Graphs (Annals of Discrete Mathematics, Vol 57)
Algorithmic Graph Theory and Perfect Graphs (Annals of Discrete Mathematics, Vol 57)
A complete complexity classification of the role assignment problem
Theoretical Computer Science - Graph colorings
Local Computations in Graphs: The Case of Cellular Edge Local Computations
Fundamenta Informaticae - SPECIAL ISSUE ON ICGT 2004
The clique-separator graph for chordal graphs
Discrete Applied Mathematics
Finite planar emulators for K4,5-4K2 and K1,2,2,2 and Fellows' Conjecture
European Journal of Combinatorics
Comparing Universal Covers in Polynomial Time
Theory of Computing Systems - Special Issue: Symposium on Computer Science; Guest Editors: Sergei Artemov, Volker Diekert and Alexander Razborov
Graph labelings derived from models in distributed computing
WG'06 Proceedings of the 32nd international conference on Graph-Theoretic Concepts in Computer Science
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A homomorphism from a graph G to a graph R is locally surjective if its restriction to the neighborhood of each vertex of G is surjective. Such a homomorphism is also called an R-role assignment of G. Role assignments have applications in distributed computing, social network theory, and topological graph theory. The Role Assignment problem has as input a pair of graphs (G, R) and asks whether G has an R-role assignment. This problem is NP-complete already on input pairs (G, R) where R is a path on three vertices. So far, the only known non-trivial tractable case consists of input pairs (G, R) where G is a tree. We present a polynomial time algorithm that solves Role Assignment on all input pairs (G, R) where G is a proper interval graph. Thus we identify the first graph class other than trees on which the problem is tractable. As a complementary result, we show that the problem is Graph Isomorphism-hard on chordal graphs, a superclass of proper interval graphs and trees.