The Maximum Edge-Disjoint Paths Problem in Bidirected Trees
نویسندگان
چکیده
A bidirected tree is the directed graph obtained from an undirected tree by replacing each undirected edge by two directed edges with opposite directions. Given a set of directed paths in a bidirected tree, the goal of the maximum edge-disjoint paths problem is to select a maximum-cardinality subset of the paths such that the selected paths are edge-disjoint. This problem can be solved optimally in polynomial time for bidirected trees of constant degree, but is MAX SNP-hard for bidirected trees of arbitrary degree. For every xed " > 0, a polynomial-time (5=3+")-approximation algorithm is presented.
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عنوان ژورنال:
- SIAM J. Discrete Math.
دوره 14 شماره
صفحات -
تاریخ انتشار 2001