std::set<Key,Compare,Allocator>::rbegin, std::set<Key,Compare,Allocator>::crbegin

From cppreference.com
< cpp‎ | container‎ | set

 
 
Containers library
Sequence
(C++11)
Associative
Unordered associative
Adaptors
Views
(C++20)
 
 
reverse_iterator rbegin();
(until C++11)
reverse_iterator rbegin() noexcept;
(since C++11)
const_reverse_iterator rbegin() const;
(until C++11)
const_reverse_iterator rbegin() const noexcept;
(since C++11)
const_reverse_iterator crbegin() const noexcept;
(since C++11)

Returns a reverse iterator to the first element of the reversed set. It corresponds to the last element of the non-reversed set. If the set is empty, the returned iterator is equal to rend().

range-rbegin-rend.svg

Parameters

(none)

Return value

Reverse iterator to the first element.

Complexity

Constant.

Notes

Because both iterator and const_iterator are constant iterators (and may in fact be the same type), it is not possible to mutate the elements of the container through an iterator returned by any of these member functions.

Example

#include <iostream>
#include <set>
 
int main()
{
    std::set<unsigned> rep{1, 2, 3, 4, 1, 2, 3, 4};
 
    for (auto it = rep.crbegin(); it != rep.crend(); ++it) {
        for (auto n = *it; n > 0; --n)
            std::cout << "⏼" << ' ';
        std::cout << '\n';
    }
}

Output:

⏼ ⏼ ⏼ ⏼ 
⏼ ⏼ ⏼ 
⏼ ⏼ 
⏼

See also

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