std::array<T,N>::back

 

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std::array

Member types
Member functions
Element access array::at array::operator[]    array::front array::back array::data Operations array::fill array::swap	Iterators array::beginarray::cbegin array::endarray::cend array::rbeginarray::crbegin    array::rendarray::crend	Capacity array::empty array::size array::max_size
Non-member functions
operator==operator<=> (C++20) get(std::array) swap(std::array) to_array (C++20)	operator|=operator<operator>operator<=operator>= (until C++20)(until C++20)(until C++20)(until C++20)(until C++20)
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tuple_element<std::array>
Deduction guides (C++17)

 

reference back();	(1)	(since C++11) (constexpr since C++17)
const_reference back() const;	(2)	(since C++11) (constexpr since C++14)

Returns a reference to the last element in the container.

If empty() is true, the behavior is undefined.	(until C++26)
If empty() is true: If the implementation is hardened, a contract violation occurs. Moreover, if the contract-violation handler returns under “observe” evaluation semantic, the behavior is undefined. If the implementation is not hardened, the behavior is undefined.	(since C++26)

Return value

Reference to the last element.

Complexity

Constant.

Notes

For a non-empty container c, the expression c.back() is equivalent to *std::prev(c.end().

Example

Run this code

#include <cassert>
#include <array>
 
int main()
{
    std::array<char, 4> letters{'a', 'b', 'c', 'd'};
    assert(letters.back() == 'd');
}

See also

front	access the first element (public member function)
rbegincrbegin	returns a reverse iterator to the beginning (public member function)
endcend	returns an iterator to the end (public member function)

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