Vertex-Cover Problem

A vertex cover of an undirected graph G = (V, E) is a subset V' $\subseteq$ V such that each edge in E is incident on at least one of the vertices in V'.

VC = is a graph, and such that and , either $u \in V'$ or $v \in V'$ (or both) }

VC = {$\langle$G, k$\rangle$$\mid$ graph G has vertex cover of size k}