Minimum Cost Homomorphism Dichotomy for Oriented Cycles
نویسندگان
چکیده
منابع مشابه
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 costs ci (u), i ∈ V (H), then the cost of the homomorphism f is ∑ u∈V (D) c f (u)(u). For each fixed digraph H , we have the minimum cost homomorphism problem for H (abbreviated MinHOM(H )). The problem is to decide, for an ...
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For digraphs D and H, a homomorphism of D to H is a mapping f : V (D)→V (H) such that uv ∈ A(D) implies f(u)f(v) ∈ A(H). Suppose D and H are two digraphs, and ci(u), u ∈ V (D), i ∈ V (H), are nonnegative real costs. The cost of the homomorphism f of D to H is ∑ u∈V (D) cf(u)(u). The minimum cost homomorphism for a fixed digraph H, denoted by MinHOM(H), asks whether or not an input digraphD, wit...
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In the constraint satisfaction problem (CSP ), the aim is to find an assignment of values to a set of variables subject to specified constraints. In the minimum cost homomorphism problem (MinHom), one is additionally given weights cva for every variable v and value a, and the aim is to find an assignment f to the variables that minimizes ∑ v cvf(v). Let MinHom (Γ) denote the MinHom problem para...
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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). In the minimum cost homomorphism problem we associate costs ci(u), u ∈ V (G), i ∈ V (H) with the mapping of u to i and the cost of a homomorphism f is defined ∑ u∈V (G) cf(u)(u) accordingly. Here the minimum cost homomorphism problem for a fixed digraph H , denoted by MinHOM...
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In the constraint satisfaction problem (CSP ), the aim is to find an assignment of values to a set of variables subject to specified constraints. In the minimum cost homomorphism problem (MinHom), one is additionally given weights cva for every variable v and value a, and the aim is to find an assignment f to the variables that minimizes ∑ v cvf(v). Let MinHom (Γ) denote the MinHom problem para...
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ژورنال
عنوان ژورنال: Graphs and Combinatorics
سال: 2009
ISSN: 0911-0119,1435-5914
DOI: 10.1007/s00373-009-0853-9