SAT solving

Conflict

A clause made false by the current partial assignment.

Definition

Conflict

A conflict occurs when every literal in a clause is false under the current assignments.

The conflict shows that the current branch cannot extend to a model. CDCL uses the implication trail to find which earlier choices caused it.

01

Example

The clause a or b conflicts with the assignments a = false and b = false.

02

Important distinction

A conflict rejects one search branch. It establishes global unsat only when search and learning rule out every branch.

After reading this article, you should be able to

  • Define Conflict in the sense used on this site.
  • Find the clause responsible for a conflict in a partial assignment.