Approximation algorithms for metric tree cover and generalized tour and tree covers
نویسندگان
چکیده
منابع مشابه
Approximation algorithms for metric tree cover and generalized tour and tree covers
Given a weighted undirected graph G = (V, E), a tree (respectively tour) cover of an edge-weighted graph is a set of edges which forms a tree (resp. closed walk) and covers every other edge in the graph. The tree (resp. tour) cover problem is of finding a minimum weight tree (resp. tour) cover of G. Arkin, Halldórsson and Hassin (1993) give approximation algorithms with factors respectively 3.5...
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The tree and tour cover problems on an edge-weighted graph are to compute a minimum weight tree and closed walk, respectively, whose vertices form a vertex cover. Both problems are NP-hard. In this note we give strongly polynomial time, constant factor approximation algorithms for both problems. An interesting feature of our algorithms is how they combine approximations of other problems, namel...
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ژورنال
عنوان ژورنال: RAIRO - Operations Research
سال: 2007
ISSN: 0399-0559,1290-3868
DOI: 10.1051/ro:2007025