Synopsis

namespace std {
    namespace tr1 {
    // DECLARATIONS
template <class Key, class Ty, class Hash, class Pred, class Alloc>
    class unordered_map;
template <class Key, class Ty, class Hash, class Pred, class Alloc>
    class unordered_multimap;

    // TEMPLATE FUNCTIONS
template <class Key, class Ty, class Hash, class Pred, class Alloc>
    void swap(
        unordered_map<Key, Ty, Hash, Pred, Alloc>& left,
        unordered_map<Key, Ty, Hash, Pred, Alloc>& right);
template <class Key, class Ty, class Hash, class Pred, class Alloc>
    void swap(
        unordered_multimap<Key, Ty, Hash, Pred, Alloc>& left,
        unordered_multimap<Key, Ty, Hash, Pred, Alloc>& right);
    } // namespace tr1
} // namespace std