Difference between revisions of "cpp/container/array/front"
From cppreference.com
m (Shorten template names. Use {{lc}} where appropriate.) |
(langlinks) |
||
Line 1: | Line 1: | ||
{{include page|cpp/container/front|array}} | {{include page|cpp/container/front|array}} | ||
− | + | {{langlinks|de|es|fr|it|ja|pt|ru|zh}} | |
− | + | ||
− | + | ||
− | + | ||
− | + | ||
− | + | ||
− | + | ||
− | + |
Latest revision as of 10:56, 25 September 2020
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, 4>:
Run this code
#include <cassert> #include <array> int main() { std::array<char, 4> letters{'a', 'b', 'c', 'd'}; assert(letters.front() == 'a'); }
[edit] See also
access the last element (public member function) | |
returns a reverse iterator to the end (public member function) | |
returns an iterator to the beginning (public member function) | |
direct access to the underlying contiguous storage (public member function) |