What is the goal of the AC-3 algorithm?

The AC-3 algorithm, or Arc Consistency Algorithm #3, aims to ensure that all arcs of constraints in a constraint satisfaction problem (CSP) are satisfied. It is primarily used in scenarios where variables have to satisfy certain constraints relative to one another. By enforcing arc consistency, the algorithm identifies the values that can be assigned to variables in such a way that they do not violate any constraints when considering pairs of variables. This process helps reduce the search space significantly, making it easier to find a solution or to determine if no solution exists.

The focus of AC-3 is on the relationships (or arcs) between pairs of variables in a CSP and ensures that for every value of one variable, there exists a compatible value in the related variable. Thus, the main goal revolves around satisfying these constraints and ensuring that they hold true, facilitating efficient problem-solving in AI applications that require constraint satisfaction.