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

< cpp‎ | container‎ | array

	(1)
reference front();			(until C++17)
constexpr reference front();			(since C++17)
		(2)
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 causes undefined behavior.

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>:

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

Output: