std::deque<T,Allocator>::back

 

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std::deque

Member types
Member functions
deque::deque deque::~deque deque::operator= deque::assign deque::assign_range (C++23)   deque::get_allocator Element access deque::at deque::operator[] deque::front deque::back Iterators deque::begindeque::cbegin (C++11) deque::enddeque::cend (C++11) deque::rbegindeque::crbegin (C++11) deque::renddeque::crend (C++11)	Capacity deque::empty deque::size deque::max_size deque::shrink_to_fit (DR*) Modifiers deque::clear deque::insert deque::insert_range (C++23) deque::emplace deque::erase deque::push_front deque::emplace_front (C++11) deque::prepend_range (C++23) deque::pop_front deque::push_back deque::emplace_back (C++11) deque::append_range (C++23) deque::pop_back deque::resize deque::swap
Non-member functions
operator==operator<=> (C++20) swap(std::deque) erase(std::deque)erase_if(std::deque) (C++20)(C++20)	operator!=operator<operator>operator<=operator>= (until C++20)(until C++20)(until C++20)(until C++20)(until C++20)
Deduction guides(C++17)

 

reference back();	(1)
const_reference back() const;	(2)

Returns a reference to the last element in the container.

Calling back on an empty container causes undefined behavior.

Parameters

(none)

Return value

Reference to the last element.

Complexity

Constant.

Notes

For a non-empty container c, the expression c.back() is equivalent to *std::prev(c.end()).

Example

Run this code

#include <cassert>
#include <deque>
 
int main()
{
    std::deque<char> letters{'a', 'b', 'c', 'd'};
    assert(letters.back() == 'd');
}

See also

front	access the first element (public member function)
rbegincrbegin (C++11)	returns a reverse iterator to the beginning (public member function)
endcend (C++11)	returns an iterator to the end (public member function)