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

From cppreference.com
< cpp‎ | container‎ | array
 
 
 
 
reference front();
(1) (since C++11)
(constexpr since C++17)
const_reference front() const;
(2) (since C++11)
(constexpr since C++14)

Returns a reference to the first element in the container.

Calling front on an empty container causes undefined behavior.

Contents

[edit] Parameters

(none)

[edit] Return value

Reference to the first element.

[edit] Complexity

Constant.

[edit] Notes

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

[edit] 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:

The first character is 'a'.

[edit] See also

access the last element
(public member function) [edit]