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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>:

#include <array>
#include <iostream>
 
int main()
{
    std::array<char> 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

See also

access the last element
(public member function)

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