Здравствуйте, ssm, Вы писали:

ssm>hash_map is useful for "dictionaries" where the order of elements is irrelevant. If it is important for the elements to be in a particular order, however, then map is more appropriate

Хм, вот оно как... Верно меня
"Stores and retrieves data quickly from a collection in which each element is a pair that has a sort key whose value is unique and an associated data value." ввело в заблуждение...
Спасибо!