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std::array front() method

// Non const version
constexpr reference front();

// Const version
constexpr const_reference front() const;

Returns a reference

to the first element in the container.

Calling front on an empty container results in an 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

Main.cpp
#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";
}
}
Possible output
The first character is 'o'.
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Hover to see the original license.

std::array front() method

// Non const version
constexpr reference front();

// Const version
constexpr const_reference front() const;

Returns a reference

to the first element in the container.

Calling front on an empty container results in an 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

Main.cpp
#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";
}
}
Possible output
The first character is 'o'.
This article originates from this CppReference page. It was likely altered for improvements or editors' preference. Click "Edit this page" to see all changes made to this document.
Hover to see the original license.