Generating hard SAT/CSP instances using expander graphs

In this paper we provide a new method to generate hard k-SAT instances. We incrementally construct a high girth bipartite incidence graph of the k-SAT instance. Having high girth assures high expansion for the graph, and high expansion implies high resolution width. We have extended this approach to...

ver descrição completa

Detalhes bibliográficos
Autores: Ansótegui Gil, Carlos José, Béjar Torres, Ramón, Fernàndez Camon, César, Mateu Piñol, Carles
Tipo de documento: artigo
Estado:Versión aceptada para publicación
Data de publicação:2008
País:España
Recursos:Universitat de Lleida (UdL)
Repositório:Repositori Obert UdL
OAI Identifier:oai:repositori.udl.cat:10459.1/46644
Acesso em linha:http://hdl.handle.net/10459.1/46644
Access Level:Acceso aberto
Palavra-chave:Intel·ligència artificial
Tecnologia Innovacions
Descrição
Resumo:In this paper we provide a new method to generate hard k-SAT instances. We incrementally construct a high girth bipartite incidence graph of the k-SAT instance. Having high girth assures high expansion for the graph, and high expansion implies high resolution width. We have extended this approach to generate hard n-ary CSP instances and we have also adapted this idea to increase the expansion of the system of linear equations used to generate XORSAT instances, being able to produce harder satisfiable instances than former generators.