A type that provides a bidirectional iterator that can read any const element in the multimap.
A type const_reverse_iterator cannot modify the value of an element and is use to iterate through the multimap in reverse.
The const_reverse_iterator defined by multimap points to objects of value_type, which are of type pair<const Key, Type>. The value of the key is available through the first member pair and the value of the mapped element is available through the second member of the pair.
To dereference a const_reverse_iterator crIter pointing to an element in a multimap, use the -> operator.
To access the value of the key for the element, use crIter -> first, which is equivalent to (*crIter).first. To access the value of the mapped datum for the element, use crIter -> second, which is equivalent to (*crIter).first.