NAME¶

std::flat_set::rbegin, - std::flat_set::rbegin,

Synopsis¶

reverse_iterator rbegin() noexcept; (1) (since C++23)
const_reverse_iterator rbegin() const noexcept; (2) (since C++23)
const_reverse_iterator crbegin() const noexcept; (3) (since C++23)

Returns a reverse iterator to the first element of the reversed flat_set. It
corresponds to the last element of the non-reversed flat_set. If the flat_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.

The underlying iterator of the returned reverse iterator is the end iterator. Hence
the returned iterator is invalidated if and when the end iterator is invalidated.

Example¶

// Run this code

#include <iostream>
#include <flat_set>

int main()
{
std::flat_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¶

rend returns a reverse iterator to the end
crend (public member function)
rbegin returns a reverse iterator to the beginning of a container or array
crbegin (function template)
(C++14)