template<class T>
const T& min(const T& x, const T& y);
template<class T, class Pred>
const T& min(const T& x, const T& y, Pred pr);The first template function returns y if y < x. Otherwise it returns x. T need supply only a single-argument constructor and a destructor.
The second template function behaves the same, except that it replaces operator<(X, Y) with pr(X, Y).