#include <iostream>
#include <iterator>
#include <boost/circular_buffer.hpp>

using std::cout;
using std::endl;
using std::distance;
using boost::circular_buffer;


class BufferHolder
{
  public :
   typedef int data_type;
  private:
   circular_buffer<data_type> data;
   circular_buffer<data_type>::const_iterator my_end;

  public:
   BufferHolder() :
      data(4), my_end(data.begin())
   { }
   
   void push(const data_type & value)
   {
      cout << "Current size of member circ. buffer: " << data.size() << endl;
      cout << "Current reserve of member circ. buffer: "
           << data.reserve() << endl;
      cout << "Pushing into circ. buffer" << endl;
      data.push_front(value);
      circular_buffer<data_type>::const_iterator it = data.begin();
      int amount = 25;
      for (int i=0;
           (it != my_end) && (it!=data.end())
              && (amount>0) && (i<data.capacity()-1);
           i++)
      {
         amount -= *it;
         ++it;
      }
      cout << "amount held in my buffer: " << 25 - amount << endl;
      
      my_end = it;
      cout << "Distance from begin to my_end: "
           << distance<circular_buffer<data_type>::const_iterator>(
              data.begin(), my_end) << endl;
      cout << "Distance from my_end to end: "
           << distance<circular_buffer<data_type>::const_iterator>(
              my_end, data.end()) << endl;
   }
};


int main()
{
   BufferHolder my_buffer;
   for (int i=0; i<20; ++i)
   {
      cout << "=============" << endl;
      int datum = 5+(5*(i%2));
      cout << "Pushing into my buffer: " << datum << endl;
      my_buffer.push(datum);
   }
}