Title
On guarding rectilinear domains
Abstract
We prove that guarding the vertices of a rectilinear polygon P, whether by guards lying at vertices of P, or by guards lying on the boundary of P, or by guards lying anywhere in P, is NP-hard. For the first two proofs (i.e., vertex guards and boundary guards), we construct a reduction from minimum piercing of 2-intervals. The third proof is somewhat simpler; it is obtained by adapting a known reduction from minimum line cover We also consider the problem of guarding the vertices of a 1.5D rectilinear terrain by vertex guards. We establish an interesting connection between this problem and the problem of computing a minimum clique cover in chordal graphs. This connection yields a 2-approximation algorithm for the guarding problem
Year
DOI
Venue
2006
10.1007/11785293_22
SWAT
Keywords
Field
DocType
connection yield,minimum clique cover,rectilinear polygon,boundary guard,minimum line,rectilinear domain,vertex guard,known reduction,interesting connection,rectilinear terrain,minimum piercing,chordal graph
Discrete mathematics,Approximation algorithm,Combinatorics,Polygon,Rectilinear polygon,Vertex (geometry),Chordal graph,Clique cover,Mathematical proof,Clique (graph theory),Mathematics
Conference
Volume
ISSN
ISBN
4059
0302-9743
3-540-35753-X
Citations 
PageRank 
References 
1
0.38
15
Authors
2
Name
Order
Citations
PageRank
Matthew J. Katz122519.92
Gabriel S. Roisman2241.60