std::array::front

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

Returns a reference to the first element in the container.

Calling front on an empty container is undefined.

Parameters

(none)

Return value

reference to the first element

Complexity

Constant

Notes

For a container c, the expression c.front() is equivalent to *c.begin().

Example

The following code uses front to display the first element of a std::array<char, 6>:

Run this code

#include <array>
#include <iostream>

int main()
{
    std::array<char, 6> letters {'o', 'm', 'g', 'w', 't', 'f'};

    if (!letters.empty()) {
        std::cout << "The first character is: " << letters.front() << '\n';
    }  
}

Output:

The first character is o

Language
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Concepts library (C++20)
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Regular expressions library (C++11)
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Technical Specifications

array (C++11)
vector
deque
forward_list (C++11)
list
set
multiset
map
multimap
unordered_set (C++11)
unordered_multiset (C++11)
unordered_map (C++11)
unordered_multimap (C++11)
stack
queue
priority_queue
span (C++20)