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

reverse_iterator rend();
(until C++11)
reverse_iterator rend() noexcept;
(since C++11)
const_reverse_iterator rend() const;
(until C++11)
const_reverse_iterator rend() const 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.




#include <algorithm>
#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.
    std::for_each(nums.rbegin(), nums.rend(), [](const int n) { std::cout << n << ' '; });
    std::cout << '\n';
    // Sums all integers in the deque nums (if any), printing only the result.
    std::cout << "Sum of nums: "
              << std::accumulate(nums.rbegin(), nums.rend(), 0) << '\n';
    // Prints the first fruit in the deque fruits, checking if there is any.
    if (!fruits.empty())
        std::cout << "First fruit: " << *fruits.rbegin() << '\n';
    if (empty.rbegin() == empty.rend())
        std::cout << "deque 'empty' is indeed empty.\n";


16 8 4 2 1
Sum of nums: 31
First fruit: raspberry
deque 'empty' is indeed empty.

See also

returns a reverse iterator to the beginning
(public member function)
returns a reverse end iterator for a container or array
(function template)

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