# std::end, std::cend

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< cpp‎ | iterator

Defined in header `<iterator>` |  |
| (1) |
template< class C > auto end( C& c ) -> decltype(c.end()); |  | (since C++11) (until C++17)
template< class C > constexpr auto end( C& c ) -> decltype(c.end()); |  | (since C++17)
| (1) |
template< class C > auto end( const C& c ) -> decltype(c.end()); |  | (since C++11) (until C++17)
template< class C > constexpr auto end( const C& c ) -> decltype(c.end()); |  | (since C++17)
| (2) |
template< class T, std::size_t N > T* end( T (&array)[N] ); |  | (since C++11) (until C++14)
template< class T, std::size_t N > constexpr T* end( T (&array)[N] ) noexcept; |  | (since C++14)
template< class C > constexpr auto cend( const C& c ) noexcept(/* see below */) -> decltype(std::end(c)); | (3) | (since C++14)

Returns an iterator to the end (i.e. the element after the last element) of the given container `c` or array `array`. These templates rely on C::end() having a reasonable implementation.

1) Returns exactly c.end(), which is typically an iterator one past the end of the sequence represented by `c`. If `C` is a standard Container, this returns a C::iterator when `c` is not const-qualified, and a C::const_iterator otherwise.
2) Returns a pointer to the end of the array `array`.
3) Returns exactly std::end(c), with `c` always treated as const-qualified. If `C` is a standard Container, this always returns a C::const_iterator.

### Parameters

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

### Return value

An iterator to the end of `c` or `array`. Note that the end of a container or array is defined as the element following the last valid element.

### Exceptions

3)
`noexcept` specification:
noexcept(noexcept(std::end(c)))

### Notes

In addition to being included in `<iterator>`, `std::end` and `std::cend` 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>`.

### User-defined overloads

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

std::end(std::initializer_list) (C++11) | specializes std::end (function template)
std::end(std::valarray) (C++11) | specializes std::end (function template)
begin(std::filesystem::directory_iterator)end(std::filesystem::directory_iterator) | range-based for loop support (function)
begin(std::filesystem::recursive_directory_iterator)end(std::filesystem::recursive_directory_iterator) | range-based for loop support (function)

Similar to the use of `swap` (described in Swappable), typical use of the `end` function in generic context is an equivalent of using std::end; end(arg);, which lets both the ADL-selected overloads for user-defined types and the standard library function templates to appear in the same overload set.

    template<typename Container, typename Function>
    void for_each(Container&& cont, Function f) {
        using std::begin;
        auto it = begin(cont);
        using std::end;
        auto end_it = end(cont);
        while (it != end_it) {
            f(*it);
            ++it;
        }
    }

### Example

Run this code

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

    int main()
    {
        std::vector<int> v = { 3, 1, 4 };
        if (std::find(std::begin(v), std::end(v), 5) != std::end(v)) {
            std::cout << "found a 5 in vector v!\n";
        }

        int a[] = { 5, 10, 15 };
        if (std::find(std::begin(a), std::end(a), 5) != std::end(a)) {
            std::cout << "found a 5 in array a!\n";
        }
    }

Output:

    found a 5 in array a!

### See also

begincbegin (C++11)(C++14) | returns an iterator to the beginning of a container or array (function template)

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