On Approximation Hardness of Dense TSP and other Path Problems
نویسندگان
چکیده
TSP(1,2) is the problem of nding a tour with minimum length in a complete weighted graph where each edge has length 1 or 2. Let d o satisfy 0 < d o < 1=2. We show that TSP(1,2) has no PTAS on the set of instances where the density of the subgraph spanned by the edges with length 1 is bounded below by d o. We also show that LONGEST PATH has no PTAS on the set of instances with density bounded below by d o .
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عنوان ژورنال:
- Electronic Colloquium on Computational Complexity (ECCC)
دوره 5 شماره
صفحات -
تاریخ انتشار 1998