$.$

A clique in an undirected graph G $=($V$,$ E$)$ is a subset C $$ V of vertices in which every pair of vertices is connected by an edge. $($In other words, C $$ V is a clique if for all v$,$ w in C$,$ we have $\{$v$,$ w$\}$ in E$.)$ The size of a clique C is defined to be the number of vertices in set C$.$