Refining the Basic Constraint Propagation Algorithm

Constraint propagation is the main feature of any constraint solver. This is thus of prime importance to manage constraint propagation as efficiently as possible, justifying the use of the best algorithms. But the ease of integration is also one of the concerns when implementing an algorithm in a constraint solver. This paper focuses on AC-3, which is the simplest arc consistency algorithm known so far. We propose two refinements that preserve as much as possible the ease of integration into a solver (no heavy data structure to be maintained during search), while giving some noticeable improvements in efficiency. One of the proposed refinements is analytically compared to AC-6, showing interesting properties. R

• Type: Conference
• Year: 2001
• Where: IJCAI
• Authors: Christian Bessière, Jean-Charles Régin
• Keywords: Constraint Propagation, Constraint Solver, IJCAI 2001, IJCAI 2007, Une Des