Fractional Packing of T-Joins
نویسنده
چکیده
Given a graph with nonnegative capacities on its edges, it is well known that the capacity of a minimum T -cut is equal to the value of a maximum fractional packing of T -joins. Padberg-Rao’s algorithm finds a minimum capacity T -cut but it does not produce a T -join packing, we present a polynomial combinatorial algorithm for finding an optimal T -join packing.
منابع مشابه
Packing odd T-joins with at most two terminals
Take a graph G, an edge subset Σ ⊆ E(G), and a set of terminals T ⊆ V (G) where |T | is even. The triple (G,Σ, T ) is called a signed graft. A T -join is odd if it contains an odd number of edges from Σ. Let ν be the maximum number of edge-disjoint odd T -joins. A signature is a set of the form Σ4δ(U) where U ⊆ V (G) and |U ∩ T | is even. Let τ be the minimum cardinality a T -cut or a signature...
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A graft is a graph G = (V,E) together with a set T ⊆ V of even cardinality. A T-cut of G is an edge cut δ(X) for which |X ∩T | is odd. A T-join of G is a set of edges S ⊆ E with the property that a vertex of the graph (V, S) has odd degree if and only if it is in T . A T-join packing of G is a set of pairwise disjoint T-joins. Let τ(G) be the size of the smallest T-cut of G and let ν(G) be the ...
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عنوان ژورنال:
- SIAM J. Discrete Math.
دوره 17 شماره
صفحات -
تاریخ انتشار 2004