explicit flat_multiset(container_type cont, const key_compare& comp = key_compare());
template<class Allocator>
flat_multiset(const container_type& cont, const Allocator& a);
template<class Allocator>
flat_multiset(const container_type& cont, const key_compare& comp, const Allocator& a);
template<class Allocator>
flat_multiset(sorted_equivalent_t s, const container_type& cont, const Allocator& a);
template<class Allocator>
flat_multiset(sorted_equivalent_t s, const container_type& cont,
const key_compare& comp, const Allocator& a);
template<class Allocator>
flat_multiset(const key_compare& comp, const Allocator& a);
template<class Allocator>
explicit flat_multiset(const Allocator& a);
template<class InputIterator, class Allocator>
flat_multiset(InputIterator first, InputIterator last,
const key_compare& comp, const Allocator& a);
template<class InputIterator, class Allocator>
flat_multiset(InputIterator first, InputIterator last, const Allocator& a);
template<container-compatible-range<value_type> R, class Allocator>
flat_multiset(from_range_t, R&& rg, const Allocator& a);
template<container-compatible-range<value_type> R, class Allocator>
flat_multiset(from_range_t, R&& rg, const key_compare& comp, const Allocator& a);
template<class InputIterator, class Allocator>
flat_multiset(sorted_equivalent_t, InputIterator first, InputIterator last,
const key_compare& comp, const Allocator& a);
template<class InputIterator, class Allocator>
flat_multiset(sorted_equivalent_t, InputIterator first, InputIterator last, const Allocator& a);
template<class Allocator>
flat_multiset(initializer_list<value_type> il, const key_compare& comp, const Allocator& a);
template<class Allocator>
flat_multiset(initializer_list<value_type> il, const Allocator& a);
template<class Allocator>
flat_multiset(sorted_equivalent_t, initializer_list<value_type> il,
const key_compare& comp, const Allocator& a);
template<class Allocator>
flat_multiset(sorted_equivalent_t, initializer_list<value_type> il, const Allocator& a);
template<class... Args> iterator emplace(Args&&... args);
template<class InputIterator>
void insert(InputIterator first, InputIterator last);
template<class InputIterator>
void insert(sorted_equivalent_t, InputIterator first, InputIterator last);
void swap(flat_multiset& y) noexcept;
container_type extract() &&;
void replace(container_type&& cont);
template<class Key, class Compare, class KeyContainer, class Predicate>
typename flat_multiset<Key, Compare, KeyContainer>::size_type
erase_if(flat_multiset<Key, Compare, KeyContainer>& c, Predicate pred);