explicit stack(const Container& cont);
explicit stack(Container&& cont);
template<class InputIterator>
  stack(InputIterator first, InputIterator last);
template<container-compatible-range<T> R>
  stack(from_range_t, R&& rg);
template<class Alloc> explicit stack(const Alloc& a);
template<class Alloc> stack(const container_type& cont, const Alloc& a);
template<class Alloc> stack(container_type&& cont, const Alloc& a);
template<class Alloc> stack(const stack& s, const Alloc& a);
template<class Alloc> stack(stack&& s, const Alloc& a);
template<class InputIterator, class Alloc>
  stack(InputIterator first, InputIterator last, const Alloc& alloc);
template<container-compatible-range<T> R, class Alloc>
  stack(from_range_t, R&& rg, const Alloc& a);
template<container-compatible-range<T> R>
  void push_range(R&& rg);
template<class T, class Container>
  bool operator==(const stack<T, Container>& x, const stack<T, Container>& y);
template<class T, class Container>
  bool operator!=(const stack<T, Container>& x, const stack<T, Container>& y);
template<class T, class Container>
  bool operator< (const stack<T, Container>& x, const stack<T, Container>& y);
template<class T, class Container>
  bool operator> (const stack<T, Container>& x, const stack<T, Container>& y);
template<class T, class Container>
  bool operator<=(const stack<T, Container>& x, const stack<T, Container>& y);
template<class T, class Container>
  bool operator>=(const stack<T, Container>& x, const stack<T, Container>& y);
template<class T, three_way_comparable Container>
  compare_three_way_result_t<Container>
    operator<=>(const stack<T, Container>& x, const stack<T, Container>& y);