The quantified constraint satisfaction problem (QCSP) is a natural and useful generalization of the constraint satisfaction problem (CSP) in which both universal and existential quantification of variables is permitted. Because the CSP and QCSP are in general intractable, much effort has been directed towards identifying restricted cases of these problems that are tractable in polynomial time. In this paper, we investigate restricted cases of the QCSP having 2-semilattice polymorphisms. We prove a complete classification of 2-semilattice polymorphisms, demonstrating that each gives rise to a case of the QCSP that is either tractable in polynomial time, or coNP-hard. © Springer-Verlag Berlin Heidelberg 2004.
CITATION STYLE
Chen, H. (2004). Quantified constraint satisfaction and 2-semilattice polymorphisms. Lecture Notes in Computer Science (Including Subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 3258, 168–181. https://doi.org/10.1007/978-3-540-30201-8_15
Mendeley helps you to discover research relevant for your work.