Maximal Clique Problem

Problem Description

* Input Predicates: node/1, edge/2

* Output Predicates: clique/1

This is the problem of finding a maximal clique C in an undirected graph G. That is, for each other clique C' in G, the number of nodes in C should be larger than or equal to the number of nodes in C'.

As input, a directed graph is given, encoded by facts over the predicates node/1 and edge/2, providing respectively the nodes and the edges. A solution to the problem is a maximal clique in the undirected version of the input graph (i.e., in the symmetric closure of the input graph). A solution is encoded by the predicate clique/1: the set of nodes v such that clique(v) holds should form a maximal clique.