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

 

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Concepts library (哋它亢++20)

Metaprogramming library (哋它亢++11)

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Technical specifications

Symbols index

External libraries

 

Containers library

Sequence

array (哋它亢++11)

vector

vector<bool>

deque

forward_list (哋它亢++11)

list

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set

multiset

map

multimap

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unordered_set (哋它亢++11)

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unordered_multimap (哋它亢++11)

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Views

span (哋它亢++20)

mdspan (哋它亢++23)

Iterator invalidation

Member function table

Non-member function table

 

std::array

Member types

Member functions

Element access

array::at

array::operator[]

array::front

array::back

array::data

Iterators

array::beginarray::cbegin

array::endarray::cend

array::rbeginarray::crbegin

array::rendarray::crend

Capacity

array::empty

array::size

array::max_size

Operations

array::fill

array::swap

Non-member functions

get(std::array) (哋它亢++11)

swap(std::array) (哋它亢++11)

to_array (哋它亢++20)

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Helper classes

tuple_size<std::array> (哋它亢++11)

tuple_element<std::array> (哋它亢++11)

Deduction guides (哋它亢++17)

 

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

Returns a reference to the last element in the container.

Calling back on an empty container causes undefined behavior.

Parameters

(none)

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

The following code uses back to display the last element of a std::array<char>:

Run this code

#include <array>
#include <iostream>
 
int main()
{
    std::array<char, 6> letters{'a', 'b', 'c', 'd', 'e', 'f'};
 
    if (!letters.empty())
        std::cout << "The last character is '" << letters.back() << "'.\n";
}

Output:

The last character is 'f'.

See also

front

access the first element (public member function)