Title
Simultaneous matchings: Hardness and approximation
Abstract
Given a bipartite graph G=(X@?@?D,E@?XxD), an X-perfect matching is a matching in G that covers every node in X. In this paper we study the following generalisation of the X-perfect matching problem, which has applications in constraint programming: Given a bipartite graph as above and a collection F@?2^X of k subsets of X, find a subset M@?E of the edges such that for each C@?F, the edge set M@?(CxD) is a C-perfect matching in G (or report that no such set exists). We show that the decision problem is NP-complete and that the corresponding optimisation problem is in APX when k=O(1) and even APX-complete already for k=2. On the positive side, we show that a 2/(k+1)-approximation can be found in poly(k,|X@?D|) time. We show also that such an approximation M can be found in time (k+(k2)2^k^-^2)poly(|X@?D|), with the further restriction that each vertex in D has degree at most 2 in M.
Year
DOI
Venue
2008
10.1016/j.jcss.2008.02.001
J. Comput. Syst. Sci.
Keywords
Field
DocType
corresponding optimisation problem,decision problem,perfect matchings,constraint programming,hardness of approximation,x-perfect matching,approximation m,subset m,matchings,bipartite graph,np-completeness,k subsets,hardness of approximation.,c-perfect matching,x-perfect matching problem,simultaneous matchings,optimisation,collection f,np completeness
Discrete mathematics,Decision problem,Combinatorics,Vertex (geometry),Hardness of approximation,Generalization,Constraint programming,Bipartite graph,3-dimensional matching,Mathematics,Blossom algorithm
Journal
Volume
Issue
ISSN
74
5
Journal of Computer and System Sciences
Citations 
PageRank 
References 
9
0.52
9
Authors
4
Name
Order
Citations
PageRank
Martin Kutz1996.83
khaled elbassioni247335.78
Irit Katriel317613.72
Meena Mahajan468856.90