Hardness results for approximating the bandwidth
The bandwidth of an n-vertex graph G is the minimum value b such that the vertices of G can be mapped to distinct integer points on a line without any edge being stretched to a distance more than b. Previous to the work reported here, it was known that it is NP-hard to approximate the bandwidth with...
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| Published in | Journal of computer and system sciences Vol. 77; no. 1; pp. 62 - 90 |
|---|---|
| Main Authors | , , |
| Format | Journal Article |
| Language | English |
| Published |
Elsevier Inc
2011
|
| Subjects | |
| Online Access | Get full text |
| ISSN | 0022-0000 1090-2724 |
| DOI | 10.1016/j.jcss.2010.06.006 |
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| Summary: | The bandwidth of an
n-vertex graph
G is the minimum value
b such that the vertices of
G can be mapped to distinct integer points on a line without any edge being stretched to a distance more than
b. Previous to the work reported here, it was known that it is NP-hard to approximate the bandwidth within a factor better than 3/2. We improve over this result in several respects. For certain classes of graphs (such as cycles of cliques) for which it is easy to approximate the bandwidth within a factor of 2, we show that approximating the bandwidth within a ratio better than 2 is NP-hard. For caterpillars (trees in which all vertices of degree larger than two lie on one path) we show that it is NP-hard to approximate the bandwidth within any constant, and that an approximation ratio of
c
log
n
/
log
log
n
will imply a quasi-polynomial time algorithm for NP (when
c is a sufficiently small constant). |
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| Bibliography: | ObjectType-Article-2 SourceType-Scholarly Journals-1 ObjectType-Feature-1 content type line 23 |
| ISSN: | 0022-0000 1090-2724 |
| DOI: | 10.1016/j.jcss.2010.06.006 |