std::array<T,N>::front (3) - Linux Man Pages

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

NAME

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

Synopsis


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, 6>:
// Run this code


  #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';
      }
  }

Output:


  The first character is o

See also


     access the last element
back (public member function)