std::deque::back(3)

NAME
std::deque::back - std::deque::back

Synopsis
   reference back(); (1)
   const_reference back() const; (2)
   Returns a reference to the last element in the container.
   Calling back on an empty container causes undefined behavior.

Parameters
   (none)

Return value
   Reference to the last element.

Complexity
   Constant.

Notes
   For a non-empty container c, the expression c.back() is equivalent to
   *std::prev(c.end()).

Example
   The following code uses back to display the last element of a std::deque<char>: // Run this code
 #include <deque>
 #include <iostream>
 int main()
 {
     std::deque<char> letters{'a', 'b', 'c', 'd', 'e', 'f'};
     if (!letters.empty())
         std::cout << "The last character is '" << letters.back() << "'.\n";
 }

Output:
 The last character is 'f'.

See also
   front access the first element
         (public member function)