std::rend, std::crend

 

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indirectly_movable (C++20) indirectly_movable_storable (C++20) indirectly_copyable (C++20)	indirectly_copyable_storable (C++20)   indirectly_swappable (C++20) indirectly_comparable (C++20)	permutable (C++20) mergeable (C++20) sortable (C++20)
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indirect_result_t (C++20)	projected (C++20)	projected_value_t (C++26)
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Stream iterators istream_iterator    ostream_iterator istreambuf_iterator ostreambuf_iterator	Iterator customization points ranges::iter_move (C++20) ranges::iter_swap (C++20)
Iterator operations advance distance prev (C++11)   next (C++11) ranges::advance (C++20) ranges::distance (C++20) ranges::prev (C++20) ranges::next (C++20)	Range access begincbegin (C++11)(C++14) rbegincrbegin (C++14)(C++14)   endcend (C++11)(C++14) rendcrend (C++14)(C++14)   sizessize (C++17)(C++20) empty (C++17) data (C++17)

 

Defined in header <array>
Defined in header <deque>
Defined in header <flat_map>
Defined in header <flat_set>
Defined in header <forward_list>
Defined in header <inplace_vector>
Defined in header <iterator>
Defined in header <list>
Defined in header <map>
Defined in header <regex>
Defined in header <set>
Defined in header <span>
Defined in header <string>
Defined in header <string_view>
Defined in header <unordered_map>
Defined in header <unordered_set>
Defined in header <vector>
template<class C > auto rend( C& c )-> decltype(c.rend());	(1)	(since C++14) (constexpr since C++17)
template<class C > auto rend(const C& c )-> decltype(c.rend());	(2)	(since C++14) (constexpr since C++17)
template<class T, std::size_t N > std::reverse_iterator<T*> rend( T (&array)[N]);	(3)	(since C++14) (constexpr since C++17)
template<class T > std::reverse_iterator<const T*> rend(std::initializer_list<T> il );	(4)	(since C++14) (constexpr since C++17)
template<class C > auto crend(const C& c )-> decltype(std::rend(c));	(5)	(since C++14) (constexpr since C++17)

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

1,2) Returns c.rend(), which is typically an iterator one past the reverse-end of the sequence represented by c.

1) If C is a standard Container, returns a C::reverse_iterator object.

2) If C is a standard Container, returns a C::const_reverse_iterator object.

3) Returns an std::reverse_iterator<T*> object to the reverse-end of array.

4) Returns an std::reverse_iterator<const T*> object to the reverse-end of il.

5) Returns std::end(c), with c always treated as const-qualified.

If C is a standard Container, returns a C::const_reverse_iterator object.

Parameters

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

Return value

1,2)c.rend()

3)std::reverse_iterator<T*>(array)

4)std::reverse_iterator<const T*>(il.begin())

5)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 customize the behavior of std::ranges::rend and std::ranges::crend.

(since C++20)

Notes

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

Example

Run this code

#include <algorithm>#include <iostream>#include <iterator>#include <vector>   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::vector<int> v{4, 6, -3, 9, 10};std::cout<<"\nstd::vector `v` backwards: ";std::copy(std::rbegin(v), std::rend(v), std::ostream_iterator<int>(std::cout, " "));std::cout<<'\n';}

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

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