#include <iostream>
using namespace std ;


//Abstract Class
class  Collection
{
	public:


	virtual int  getSize() = 0 ;
	virtual int getElement( int index ) = 0 ;

	void printElements()
	 {
		  int size = getSize() ;
          for( int i1=0 ; i1 < size ; i1++ )
            {
              cout << getElement( i1 ) << " " ;
		    }
		  cout << endl ;
	 }


};

class Vector : public Collection
{
	public:
      int getSize()
        {
            return 2 ;
	    }


   	 int getElement( int index )
   	  {
		  if ( index == 0 )
		    return 100 ;
		  else
		    return 200 ;
	  }



};


int main()
{

   Vector vectorObj ;
   vectorObj.printElements() ;




	return 0 ;
}