On Singleton Arc Consistency for CSPs Defined by Monotone Patterns
- Resource Type
- Working Paper
- Authors
- Carbonnel, Clement; Cohen, David A.; Cooper, Martin C.; Zivny, Stanislav
- Source
- Algorithmica 81(4) 1699-1727 (2019)
- Subject
- Computer Science - Computational Complexity
Computer Science - Artificial Intelligence
Computer Science - Discrete Mathematics
- Language
Singleton arc consistency is an important type of local consistency which has been recently shown to solve all constraint satisfaction problems (CSPs) over constraint languages of bounded width. We aim to characterise all classes of CSPs defined by a forbidden pattern that are solved by singleton arc consistency and closed under removing constraints. We identify five new patterns whose absence ensures solvability by singleton arc consistency, four of which are provably maximal and three of which generalise 2-SAT. Combined with simple counter-examples for other patterns, we make significant progress towards a complete classification.
Comment: v4: Full version of a STACS'18 paper; improved presentation