Defined in header <algorithm> (1) template< class T >
std::pair<const T&,const T&> minmax( const T& a, const T& b ); (since C++11) (until C++14) template< class T >
constexpr std::pair<const T&,const T&> minmax( const T& a, const T& b ); (since C++14) (2) template< class T, class Compare >
std::pair<const T&,const T&> minmax( const T& a, const T& b,