Title
Minimum-weight cycle covers and their approximability
Abstract
A cycle cover of a graph is a set of cycles such that every vertex is part of exactly one cycle. An L-cycle cover is a cycle cover in which the length of every cycle is in the set L@?N. We investigate how well L-cycle covers of minimum weight can be approximated. For undirected graphs, we devise non-constructive polynomial-time approximation algorithms that achieve constant approximation ratios for all sets L. On the other hand, we prove that the problem cannot be approximated with a factor of 2-@e for certain sets L. For directed graphs, we devise non-constructive polynomial-time approximation algorithms that achieve approximation ratios of O(n), where n is the number of vertices. This is asymptotically optimal: We show that the problem cannot be approximated with a factor of o(n) for certain sets L. To contrast the results for cycle covers of minimum weight, we show that the problem of computing L-cycle covers of maximum weight can, at least in principle, be approximated arbitrarily well.
Year
DOI
Venue
2007
10.1016/j.dam.2008.10.005
Clinical Orthopaedics and Related Research
Keywords
DocType
Volume
approximation ratio,approximation algorithms,asymptotically optimal,minimum weight,minimum-weight cycle cover,certain set,maximum weight,constant approximation ratio,l-cycle cover,non-constructive algorithms,set l,inapproximability,cycle cover,cycle covers,non-constructive polynomial-time approximation algorithm,directed graph
Conference
157
Issue
ISSN
ISBN
7
Discrete Applied Mathematics
3-540-74838-5
Citations 
PageRank 
References 
2
0.43
24
Authors
1
Name
Order
Citations
PageRank
Bodo Manthey1635.38