26 Containers library [containers]

26.5 Unordered associative containers [unord]

26.5.7 Class template unordered_­multiset [unord.multiset]

26.5.7.3 unordered_­multiset swap [unord.multiset.swap]

template<class Key, class Hash, class Pred, class Alloc> void swap(unordered_multiset<Key, Hash, Pred, Alloc>& x, unordered_multiset<Key, Hash, Pred, Alloc>& y) noexcept(noexcept(x.swap(y)));
Effects: As if by x.swap(y).