The Parameterized Approximability of TSP with Deadlines
نویسندگان
چکیده
منابع مشابه
Approximability of the Multiple Stack TSP
STSP seeks a pair of pickup and delivery tours in two distinct networks, where the two tours are related by LIFO contraints. We address here the problem approximability. We notably establish that asymmetric MaxSTSP and MinSTSP12 are APX, and propose a heuristic that yields to a 1/2, 3/4 and 3/2 standard approximation for respectively Max2STSP, Max2STSP12 and Min2STSP12.
متن کاملOn Parameterized Approximability
Combining classical approximability questions with parameterized complexity, we introduce a theory of parameterized approximability. The main intention of this theory is to deal with the efficient approximation of small cost solutions for optimisation problems.
متن کاملApproximability of TSP on Power Law Graphs
In this paper we study the special case of Graphic TSP where the underlying graph is a power law graph (PLG). We give a refined analysis of some of the current best approximation algorithms and show that an improved approximation ratio can be achieved for certain ranges of the power law exponent β. For the value of power law exponent β = 1.5 we obtain an approximation ratio of 1.34 for Graphic ...
متن کاملParameterized TSP: Beating the Average
In the Travelling Salesman Problem (TSP), we are given a complete graph Kn together with an integer weighting w on the edges of Kn, and we are asked to find a Hamilton cycle of Kn of minimum weight. Let h(w) denote the average weight of a Hamilton cycle of Kn for the weighting w. Vizing (1973) asked whether there is a polynomialtime algorithm which always finds a Hamilton cycle of weight at mos...
متن کاملParameterized Approximability of the Disjoint Cycle Problem
We give an fpt approximation algorithm for the directed vertex disjoint cycle problem. Given a directed graph G with n vertices and a positive integer k, the algorithm constructs a family of at least k/ρ(k) disjoint cycles of G if the graph G has a family of at least k disjoint cycles (and otherwise may still produce a solution, or just report failure). Here ρ is a computable function such that...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Theory of Computing Systems
سال: 2007
ISSN: 1432-4350,1433-0490
DOI: 10.1007/s00224-007-1347-x