uses GraphABC; 

procedure RDrawRectangle(x, y, x1, y1: real):=DrawRectangle(Round(x), Round(y), Round(x1), Round(y1));

procedure Draw(x, y, w, h: real);
begin
  RDrawRectangle(x, y, x + w, y + h); 
  
  var w1 := w / 3; 
  var h1 := h / 3; 
  RDrawRectangle(x + w1, y + h1, x + 2 * w1, y + 2 * h1);
  
  if (w1 > 3) and (h1 > 3) then 
  begin
    for var i := 0 to 2 do 
      for var j := 0 to 2 do 
        if (i <> 1) or (j <> 1) then 
          Draw(x + w1 * i, y + h1 * j, w1, h1); 
  end; 
end;

begin
  SetWindowSize(500, 500);
  
  LockDrawing();
  Draw(0, 0, Window.Width, Window.Height);
  Redraw();
end.