# List Homomorphisms to Reflexive Graphs

@article{Feder1998ListHT, title={List Homomorphisms to Reflexive Graphs}, author={Tom{\'a}s Feder and Pavol Hell}, journal={J. Comb. Theory, Ser. B}, year={1998}, volume={72}, pages={236-250} }

LetHbe a fixed graph. We introduce the following list homomorphism problem: Given an input graphGand for each vertexvofGa “list”L(v)?V(H), decide whether or not there is a homomorphismf:G?Hsuch thatf(v)?L(v) for eachv?V(G). We discuss this problem primarily in the context of reflexive graphs, i.e., graphs in which each vertex has a loop. We give a polynomial time algorithm to solve the problem whenHis an interval graph and prove that whenHis not an interval graph the problem isNP-complete. If… Expand

#### 173 Citations

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LetHbe a fixed graph. We introduce the following list homomorphism problem: Given an input graphGand for each vertexvofGa “list”L(v) V(H), decide whether or not there is a homomorphismf:G Hsuch tha...

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