std::deque

From Cppreference

C++ Standard Library
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Containers library
array (C++11) vector deque forward_list (C++11) list set multiset map multimap unordered_set (C++11) unordered_multiset (C++11) unordered_map (C++11) unordered_multimap (C++11) stack queue priority_queue
std::deque
Member functions deque::deque deque::~deque deque::operator= deque::assign deque::get_allocator Element access deque::front deque::back Iterators deque::begin deque::cbegin (C++11) deque::end deque::cend (C++11) deque::rbegin deque::crbegin (C++11) deque::rend deque::crend (C++11) Capacity deque::empty deque::size deque::max_size deque::shrink_to_fit Modifiers deque::clear deque::insert deque::emplace deque::erase deque::push_front deque::emplace_front deque::pop_front deque::push_back deque::emplace_back deque::pop_back deque::resize deque::swap

Defined in header <deque>
template<     class T,     class Allocator = std::allocator<T> > class deque;

Double-ended queues (or deques) are similar to vectors, except that they allow fast insertions and deletions at both the beginning and the end of the container and that they are not required to be contiguous.

Deques are commonly implemented as lists of individual dynamically allocated arrays of some convenient size, e.g. memory page size. This guarantees constant time access, amortized constant time insertion and deletion at either end of the deque (a new array may have to be allocated), and linear time insertion and deletion from the middle of the deque.

Contents 1 Member types 2 Member functions 2.1 Element access 2.2 Iterators 2.3 Capacity 2.4 Modifiers 3 Non-member functions

[edit] Member types

Member type	Definition
value_type	T
allocator_type	Allocator
size_type	Unsigned integral type (usually size_t)
difference_type	Signed integer type (usually ptrdiff_t)
reference	Allocator::reference (pre-C++11 version) value_type& (C++11 version)
const_reference	Allocator::const_reference (pre-C++11 version) const value_type& (C++11 version)
pointer	T* (pre-C++11 version) std::allocator_traits<Allocator>::pointer (C++11 version)
const_pointer	const T* (pre-C++11 version) std::allocator_traits<Allocator>::const_pointer (C++11 version)
iterator	Random access iterator
const_iterator	Constant random access iterator
reverse_iterator	std::reverse_iterator<iterator>
const_reverse_iterator	std::reverse_iterator<const_iterator>

[edit] Member functions

(constructor)	constructs the deque (public member function)
(destructor)	destructs the deque (public member function)
operator=	assigns values to the container (public member function)
assign	assigns values to the container (public member function)
get_allocator	returns the associated allocator (public member function)
Element access
at	access specified element with bounds checking (public member function)
operator[]	access specified element (public member function)
front	access the first element (public member function)
back	access the last element (public member function)
Iterators
begin cbegin	returns an iterator to the beginning (public member function)
end cend	returns an iterator to the end (public member function)
rbegin crbegin	returns a reverse iterator to the beginning (public member function)
rend crend	returns a reverse iterator to the end (public member function)
Capacity
empty	checks whether the container is empty (public member function)
size	returns the number of elements (public member function)
max_size	returns the maximum possible number of elements (public member function)
shrink_to_fit (C++11)	reduces memory usage by freeing unused memory (public member function)
Modifiers
clear	clears the contents (public member function)
insert	inserts elements (public member function)
emplace (C++11)	constructs element in-place (public member function)
erase	erases elements (public member function)
push_back	inserts elements to the end (public member function)
emplace_back (C++11)	constructs elements in-place at the end (public member function)
pop_back	removes the last element (public member function)
push_front	inserts elements to the beginning (public member function)
emplace_front (C++11)	constructs elements in-place at the beginning (public member function)
pop_front	removes the first element (public member function)
resize	changes the number of elements stored (public member function)
swap	swaps the contents (public member function)

[edit] Non-member functions

operator== operator!= operator< operator<= operator> operator>=	lexicographically compares the values in the container (function)
std::swap(std::deque)	specializes the std::swap() algorithm (function template)