std::deque<T,Allocator>::rend, std::deque<T,Allocator>::crend

 

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std::deque

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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
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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)

 

reverse_iterator rend();	(1)	(noexcept since C++11)
const_reverse_iterator rend() const;	(2)	(noexcept since C++11)
const_reverse_iterator crend() const noexcept;	(3)	(since C++11)

Returns a reverse iterator to the element following the last element of the reversed deque. It corresponds to the element preceding the first element of the non-reversed deque. This element acts as a placeholder, attempting to access it results in undefined behavior.

Return value

Reverse iterator to the element following the last element.

Complexity

Constant.

Notes

libc++ backports crend() to C++98 mode.

Example

Run this code

#include <algorithm>
#include <cassert>
#include <iostream>
#include <numeric>
#include <string>
#include <deque>

int main()
{
    std::deque<int> nums{1, 2, 4, 8, 16};
    std::deque<std::string> fruits{"orange", "apple", "raspberry"};
    std::deque<char> empty;

    // Print deque nums.
    std::for_each(nums.crbegin(), nums.crend(),
                  [](const int n) { std::cout << n << ' '; });
    std::cout << '\n';

    // Sum all integers in the deque nums, printing only the result.
    std::cout << "Sum of nums: "
              << std::accumulate(nums.crbegin(), nums.crend(), 0) << '\n';

    // Print the last fruit in the deque fruits, checking if there is any.
    if (!fruits.empty())
        std::cout << "Last fruit: " << *fruits.crbegin() << '\n';

    if (empty.crbegin() == empty.crend())
        std::cout << "deque ‘empty’ is indeed empty.\n";

    // Modify the last element in nums.
    *nums.rbegin() = 32;
    assert(*nums.crbegin() == 32);
}

Output:

16 8 4 2 1
Sum of nums: 31
Last fruit: raspberry
deque ‘empty’ is indeed empty.

See also

rbegincrbegin (C++11)	returns a reverse iterator to the beginning (public member function)
rendcrend (C++14)	returns a reverse end iterator for a container or array (function template)