<hash_map>

Article
01/02/2018

The latest version of this topic can be found at <hash_map>.

NOTE]

This header is obsolete. The alternative is <unordered_map>.

Defines the container template classes hash_map and hash_multimap and their supporting templates.

In Visual C++ .NET 2003, members of the <hash_map> and <hash_set> header files are no longer in the std namespace, but rather have been moved into the stdext namespace. See stdext Namespace for more information.

Syntax

#include <hash_map>

Operators

Hash_map version	Hash_multimap version	Description
operator!= (hash_map)	operator!= (hash_multimap)	Tests if the hash_map or hash_multimap object on the left side of the operator is not equal to the hash_map or hash_multimap object on the right side.
operator== (hash_map)	operator== (hash_multimap)	Tests if the hash_map or hash_multimap object on the left side of the operator is equal to the hash_map or hash_multimap object on the right side.

Specialized Template Functions

Hash_map version	Hash_multimap version	Description
swap (hash_map)	swap (hash_multimap)	Exchanges the elements of two hash_maps or hash_multimaps.

Classes

hash_compare Class	Describes an object that can be used by any of the hash associative containers — hash_map, hash_multimap, hash_set, or hash_multiset — as a default Traits parameter object to order and hash the elements they contain.
value_compare Class	Provides a function object that can compare the elements of a hash_map by comparing the values of their keys to determine their relative order in the hash_map.
hash_map Class	Used for the storage and fast retrieval of data from a collection in which each element is a pair that has a sort key whose value is unique and an associated data value.
hash_multimap Class	Used for the storage and fast retrieval of data from a collection in which each element is a pair that has a sort key whose value need not be unique and an associated data value.

Requirements

Header: <hash_map>

Namespace: stdext