NAME¶

std::rend,std::crend - std::rend,std::crend

Synopsis¶

Defined in header <array>
Defined in header <deque>
Defined in header <forward_list>
Defined in header <iterator>
Defined in header <list>
Defined in header <map>
Defined in header <regex>
Defined in header <set>
Defined in header <span> (since
C++20)
Defined in header <string>
Defined in header <string_view> (since
C++17)
Defined in header <unordered_map>
Defined in header <unordered_set>
Defined in header <vector>
template< class C > (since
auto rend( C& c ) -> C++14)
decltype(c.rend()); (until
C++17)
template< class C > (since
constexpr auto rend( C& c ) -> C++17)
decltype(c.rend());
template< class C > (since
auto rend( const C& c ) -> C++14)
decltype(c.rend()); (until
C++17)
template< class C > (since
constexpr auto rend( const C& c ) C++17)
-> decltype(c.rend());
template< class T, std::size_t N (since
> C++14)
std::reverse_iterator<T*> rend( T (until
(&array)[N] ); C++17)
template< class T, std::size_t N
> (1) (since
constexpr C++17)
std::reverse_iterator<T*> rend( T
(&array)[N] ); (1)
template< class T > (since
std::reverse_iterator<const T*> C++14)
rend( std::initializer_list<T> il (until
); (2) C++17)
template< class T >
constexpr (since
std::reverse_iterator<const T*> C++17)
rend( std::initializer_list<T> il (3)
);
template< class C > (since
auto crend( const C& c ) -> C++14)
decltype(std::rend(c)); (until
(4) C++17)
template< class C > (since
constexpr auto crend( const C& c C++17)
) -> decltype(std::rend(c));

Returns an iterator to the reverse-end of the given range.

1) Returns an iterator to the reverse-end of the possibly const-qualified container
or view c.
2) Returns std::reverse_iterator<T*> to the reverse-end of the array array.
3) Returns std::reverse_iterator<const T*> to the reverse-end of the
std::initializer_list il.
4) Returns an iterator to the reverse-end of the const-qualified container or view
c.

range-rbegin-rend.svg

Parameters¶

c - a container or view with a rend member function
array - an array of arbitrary type
il - an initializer_list

Return value¶

1) c.rend()
2) std::reverse_iterator<T*>(array)
3) std::reverse_iterator<const T*>(il.begin())
4) c.rend()

Exceptions¶

May throw implementation-defined exceptions.

Overloads

Custom overloads of rend may be provided for classes and enumerations that do not
expose a suitable rend() member function, yet can be iterated.

Overloads of rend found by argument-dependent lookup can be used to (since C++20)
customize the behavior of std::ranges::rend and std::ranges::crend.

Notes¶

The overload for std::initializer_list is necessary because it does not have a
member function rend.

Example¶

// Run this code

#include <iostream>
#include <vector>
#include <iterator>
#include <algorithm>

int main()
{
int a[] = {4, 6, -3, 9, 10};
std::cout << "C-style array `a` backwards: ";
std::copy(std::rbegin(a), std::rend(a), std::ostream_iterator<int>(std::cout, " "));

auto il = { 3, 1, 4 };
std::cout << "\nstd::initializer_list `il` backwards: ";
std::copy(std::rbegin(il), std::rend(il), std::ostream_iterator<int>(std::cout, " "));

std::cout << "\nstd::vector `v` backwards: ";
std::vector<int> v = {4, 6, -3, 9, 10};
std::copy(std::rbegin(v), std::rend(v), std::ostream_iterator<int>(std::cout, " "));
}

Output:¶

C-style array `a` backwards: 10 9 -3 6 4
std::initializer_list `il` backwards: 4 1 3
std::vector `v` backwards: 10 9 -3 6 4

See also¶

end
cend returns an iterator to the end of a container or array
(C++11) (function template)
(C++14)
rbegin returns a reverse iterator to the beginning of a container or array
crbegin (function template)
(C++14)
begin
cbegin returns an iterator to the beginning of a container or array
(C++11) (function template)
(C++14)
ranges::rend returns a reverse end iterator to a range
(C++20) (customization point object)
ranges::crend returns a reverse end iterator to a read-only range
(C++20) (customization point object)