The Container Classes

The containers defined by the STL are shown here:

Container	Description	Required Header
bitset	A set of bits	<bitset>
deque	A double-ended queue	<deque>
list	A linear list	<list>
map	Stores key/value pairs in which each key is associated with only one value	<map>
multimap	Stores key/value pairs in which one key may be associated with two or more values	<map>
multiset	A set in which each element is not necessarily unique	<set>
priority_queue	A priority queue	<queue>
queue	A queue	<queue>
set	A set in which each element is unique	<set>
stack	A stack	<stack>
vector	A dynamic array	<vector>

Each of the containers is summarized in the following sections. Since the containers are implemented using template classes, various placeholder data types are used. In the descriptions, the generic type T represents the type of data stored by a container.

Since the names of the placeholder types in a template class are arbitrary, the container classes declare typedefed versions of these types. This makes the type names concrete. Here are the typedef names used by the container classes:

size_type	Some integral type roughly equivalent to size_t
reference	A reference to an element
const_reference	A const reference to an element
difference_type	Can represent the difference between two addresses
iterator	An iterator
const_iterator	A const iterator
reverse_iterator	A reverse iterator
const_reverse_iterator	A const reverse iterator
value_type	The type of a value stored in a container (often the same as the generic type T)
allocator_type	The type of the allocator
key_type	The type of a key
key_compare	The type of a function that compares two keys
mapped_type	The type of value stored in a map (same as the generic type T)
value_compare	The type of a function that compares two values
pointer	The type of a pointer
const_pointer	The type of a const pointer
container_type	The type of a container