\(\sc{TRAVELING}\ \sc{SALESMAN}\ (\sc{TSP}) \ \) Given a list of cities \(V\), the integer distance \(d(u,v)\) between each pair of cities \(u,v \in V\), and a budget  \(b \in \mathbb{N}\), is there a tour visiting each city exactly once and returning to the starting city of total distance \(\leq b\)?