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

reference back();		(until C++17)
constexpr reference back();		(since C++17)
const_reference back() const;		(until C++14)
constexpr const_reference back() const;		(since C++14)

Returns 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

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array (C++11)
vector
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list
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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
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array::empty
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array::fill
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get
std::swap
to_array (C++20)
operator==operator!=operator<operator>operator<=operator>=operator<=> (until C++20)(until C++20)(until C++20)(until C++20)(until C++20)(C++20)
Helper classes
tuple_size
tuple_element
Deduction guides(C++17)