# std::rend, std::crend

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< cpp‎ | iterator

Defined in header `<iterator>` |  |
| (1) |
template< class C > auto rend( C& c ) -> decltype(c.rend()); |  | (since C++14) (until C++17)
template< class C > constexpr auto rend( C& c ) -> decltype(c.rend()); |  | (since C++17)
| (1) |
template< class C > auto rend( const C& c ) -> decltype(c.rend()); |  | (since C++14) (until C++17)
template< class C > constexpr auto rend( const C& c ) -> decltype(c.rend()); |  | (since C++17)
| (2) |
template< class T, size_t N > reverse_iterator<T*> rend( T (&array)[N] ); |  | (since C++14) (until C++17)
template< class T, size_t N > constexpr reverse_iterator<T*> rend( T (&array)[N] ); |  | (since C++17)
| (3) |
template< class C > auto crend( const C& c ) -> decltype(std::rend(c)); |  | (since C++14) (until C++17)
template< class C > constexpr auto crend( const C& c ) -> decltype(std::rend(c)); |  | (since C++17)

Returns an iterator to the reverse-end of the given container `c` or array `array`.

1) Returns a possibly const-qualified iterator to the reverse-end of the container `c`.
2) Returns std::reverse_iterator<T*> to the reverse-end of the array `array`.
3) Returns a const-qualified iterator to the reverse-end of the container `c`.

### Parameters

c | - | a container with a `rend` method
array | - | an array of arbitrary type

### Return value

An iterator to the reverse-end of `c` or `array`

### Notes

In addition to being included in `<iterator>`, `std::rend` and `std::crend` are guaranteed to become available if any of the following headers are included: `<array>`, `<deque>`, `<forward_list>`, `<list>`, `<map>`, `<regex>`, `<set>`, `<span>` (since C++20), `<string>`, `<string_view>` (since C++17), `<unordered_map>`, `<unordered_set>`, and `<vector>`.

### Overloads

Custom overloads of `rend` may be provided for classes that do not expose a suitable `rend()` member function, yet can be iterated. The following overload is already provided by the standard library:

rend(std::initializer_list) (C++14) | specializes std::rend (function)

### Example

Run this code

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

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

        std::cout << "\nVector 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:

    Array backwards: 10 9 -3 6 4
    Vector backwards: 10 9 -3 6 4

### See also

end cend (C++11)(C++14) | returns an iterator to the end of a container or array (function template)
rbegin crbegin (C++14) | returns a reverse iterator to a container or array (function template)
begin cbegin (C++11)(C++14) | returns an iterator to the beginning of a container or array (function template)

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