Return a pair of iterators providing modifiable access to the sequence of value_type objects in this unordered multimap with a key equivalent to the specified key, where the first iterator is positioned at the start of the sequence, and the second is positioned one past the end of the sequence. If this unordered multimap contains no value_type objects with a key equivalent to key, then the two returned iterators will have the same value.
Declared in <bslstl_unorderedmultimap.h>
bsl::pair<unordered_multimap<KEY, VALUE, HASH, EQUAL, ALLOCATOR>::iterator, unordered_multimap<KEY, VALUE, HASH, EQUAL, ALLOCATOR>::iterator>
equal_range(key_type const& key);