The Steiner tree problem on graphs: Inapproximability results
نویسندگان
چکیده
The Steiner tree problem on weighted graphs seeks a minimum weight subtree containing a given subset of the vertices (terminals). We show that it is NP-hard to approximate the Steiner tree problem within a factor 96/95. Our inapproximability results are stated in a parametric way, and explicit hardness factors would be improved automatically providing gadgets and/or expanders with better parameters.
منابع مشابه
Improved Inapproximability Results for Steiner Tree via Long Code Based Reductions
The best algorithm for approximating Steiner tree has performance ratio ln(4)+ǫ ≈ 1.386 [J. Byrka et al., Proceedings of the 42th Annual ACM Symposium on Theory of Computing (STOC), 2010, pp. 583-592], whereas the inapproximability result stays at the factor 96 95 ≈ 1.0105 [M. Chleb́ık and J. Chleb́ıková, Proceedings of the 8th Scandinavian Workshop on Algorithm Theory (SWAT), 2002, pp. 170-179]....
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عنوان ژورنال:
- Theor. Comput. Sci.
دوره 406 شماره
صفحات -
تاریخ انتشار 2008