Title
On Covering Problems of Codes
Abstract
LetC be a binary code of lengthn (i.e., a subset of {0, 1} n ). TheCovering Radius of C is the smallest integerr such that each vector in {0, 1} n is at a distance at mostr from some code word. Our main result is that the decision problem associated with the Covering Radius of arbitrary binary codes is NP-complete. This result is established as follows. TheRadius of a binary codeC is the smallest integerr such thatC is contained in a radius-r ball of the Hamming metric space 〈{0, 1} n ,d〉. It is known [K] that the problems of computing the Radius and the Covering Radius are equivalent. We show that the 3SAT problem is polynomially reducible to the Radius decision problem. A central tool in our reduction is a metrical characterization of the set ofdoubled vectors of length 2n: {v=(v 1 v 2 …v 2n ) | ∀i:v 2i =v 2i−1}. We show that there is a setY ⊂ {0, 1}2n such that for everyv ε {0, 1}2n :v is doubled iffY is contained in the radius-n ball centered atv; moreover,Y can be constructed in time polynomial inn.
Year
DOI
Venue
1997
10.1007/BF02679443
Theory Comput. Syst.
Keywords
Field
DocType
Linear Code,Covering Problem,Code Word,Covering Radius,Minimum Radius
Discrete mathematics,Decision problem,Combinatorics,Covering code,Binary code,Code word,Linear code,Mathematics,Closest string,Covering problems
Journal
Volume
Issue
ISSN
30
2
1432-4350
Citations 
PageRank 
References 
80
4.60
2
Authors
2
Name
Order
Citations
PageRank
Moti Frances1845.20
Ami Litman224049.78