Shifting/aligning/rotating a circular buffer to zero in-place

Question

I\'m using a circular buffer to push data onto either end of a list. After I\'m done I want to align the buffer so the first element in the list is at position zero and can be u

Answer 1

This algorithm taken from the std::rotate implementation on cplusplus.com is quite nice:

template 
  void rotate (ForwardIterator first, ForwardIterator middle,
               ForwardIterator last)
{
  ForwardIterator next = middle;
  while (first!=next)
  {
    swap (*first++,*next++);
    if (next==last) next=middle;
    else if (first==middle) middle=next;
  }
}

http://www.cplusplus.com/reference/algorithm/rotate/