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CORR
2007
Springer
119views Education» more  CORR 2007»
13 years 11 months ago
Minimum Cost Homomorphisms to Locally Semicomplete and Quasi-Transitive Digraphs
For digraphs G and H, a homomorphism of G to H is a mapping f : V (G)→V (H) such that uv ∈ A(G) implies f(u)f(v) ∈ A(H). If, moreover, each vertex u ∈ V (G) is associated ...
Arvind Gupta, Gregory Gutin, Mehdi Karimi, Eun Jun...
CORR
2006
Springer
128views Education» more  CORR 2006»
13 years 11 months ago
Minimum Cost Homomorphisms to Semicomplete Bipartite Digraphs
For digraphs D and H, a mapping f : V (D)V (H) is a homomorphism of D to H if uv A(D) implies f(u)f(v) A(H). If, moreover, each vertex u V (D) is associated with costs ci(u), i...
Gregory Gutin, Arash Rafiey, Anders Yeo
DAM
2008
129views more  DAM 2008»
13 years 11 months ago
Minimum cost homomorphisms to semicomplete multipartite digraphs
For digraphs D and H, a mapping f : V (D)V (H) is a homomorphism of D to H if uv A(D) implies f(u)f(v) A(H). For a fixed directed or undirected graph H and an input graph D, the...
Gregory Gutin, Arash Rafiey, Anders Yeo
ISAAC
2007
Springer
146views Algorithms» more  ISAAC 2007»
14 years 5 months ago
Bounded Tree-Width and CSP-Related Problems
We study the complexity of structurally restricted homomorphism and constraint satisfaction problems. For every class of relational structures C, let LHOM(C, _) be the problem of d...
Tommy Färnqvist, Peter Jonsson
AAIM
2008
Springer
120views Algorithms» more  AAIM 2008»
14 years 6 months ago
Minimum Cost Homomorphism Dichotomy for Oriented Cycles
For digraphs D and H, a mapping f : V (D)→V (H) is a homomorphism of D to H if uv ∈ A(D) implies f(u)f(v) ∈ A(H). If, moreover, each vertex u ∈ V (D) is associated with co...
Gregory Gutin, Arash Rafiey, Anders Yeo