boolean add(int indx)
        {
            points.add(indx);
            if(bound == null)
                bound = new Rectangle(get(indx));
            else
                bound.adjustToContain(get(indx));
            return size() > M;
        }
boolean add ( int indx ) { points . add ( indx ) ; if ( bound == null ) bound = new Rectangle ( get ( indx ) ) ; else bound . adjustToContain ( get ( indx ) ) ; return size ( ) > M ; }
@param indx point to add
@return true if this node needs to be split