Past exam of the computer science course of the University of Oxford / 2021 / Artificial intelligence / 2 / b

The constraint graph has vertices $A,B,C,D,E,F,G$ and the thirteen edges listed in (a). The following original drawing distinguishes named shared-audience edges from the additional society-overlap edges. Vertex colours show one valid slot assignment; they are not extra constraints.

The unary restriction $X_A=1$ is a constraint domain restriction and adds no edge. For reference, $E$ is adjacent to every other vertex; among the remaining vertices there is a triangle $ABG$, a cycle $BDFG$, and the edge $CD$.