Advanced Approximation Algorithms ( CMU 15 - 854 B , Spring 2008 ) Lecture 10 : Group Steiner Tree problem
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We will be studying the Group Steiner tree problem in this lecture. Recall that the classical Steiner tree problem is the following. Given a weighted graphG = (V,E), a subset S ⊆ V of the vertices, and a root r ∈ V , we want to find a minimum weight tree which connects all the vertices in S to r. The weights on the edges are assumed to be positive. We will now define the Group Steiner tree problem. The input to the problem is
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تاریخ انتشار 2008