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std::end, std::cend

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>`
	(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 range.

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 or view with an `end` member function
array	-	an array of arbitrary type

Return value

An iterator to the end of the range. Note that the end of a range is defined as the element following the last valid element.

Exceptions

noexcept specification:

noexcept(noexcept(std::end(c)))

Overloads

Custom overloads of end may be provided for classes and enumerations 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) (C++17)	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;
    }
}

Overloads of end found by argument-dependent lookup can be used to customize the behavior of std::ranges::end, std::ranges::cend, and other customization pointer objects depending on std::ranges::end.

(since C++20)

Notes

(1,3) exactly reflect the behavior of C::end(). Their effects may be surprising if the member function does not have a reasonable implementation.

std::cend is introduced for unification of member and non-member range accesses. See also LWG issue 2128.

If C is a shallow-const view, std::cend may return a mutable iterator. Such behavior is unexpected for some users. See also P2276 and P2278.

Example

#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!

begincbegin (C++11)(C++14)	returns an iterator to the beginning of a container or array (function template)
ranges::end (C++20)	returns a sentinel indicating the end of a range (customization point object)
ranges::cend (C++20)	returns a sentinel indicating the end of a read-only range (customization point object)