On the Value of a Random Minimum Weight Steiner Tree

نویسندگان

  • Béla Bollobás
  • David Gamarnik
  • Oliver Riordan
  • Benny Sudakov
چکیده

Given an arbitrary weighted graph with a fixed set of vertices, the Steiner tree problem is the task of finding a minimum weight subtree containing all these vertices, where the weight of a tree is the sum of the weights of the edges it contains. Steiner trees are very well studied objects in combinatorial optimization; the interest is motivated by several practical problems such as network design and VLSI design. The Steiner tree problem is well known to be NP-complete; this separates it from the superficially similar minimum spanning tree problem, for which there is a simple polynomial time algorithm. Most of the theoretical work on the Steiner tree problem concerns obtaining approximation algorithms. Currently, the best approximation factor is 1.55, obtained by Robins and Zelikovsky [17]. Arora [2] showed that

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عنوان ژورنال:
  • Combinatorica

دوره 24  شماره 

صفحات  -

تاریخ انتشار 2004