Program Sito;
uses Graph;
var  karta,tryb,n,x,y,bok,gr:integer;
begin
  karta:=detect;
  initGraph(karta,tryb,'');
  n:=1;
  gr:=1;
  bok:=256;
  rectangle(0,0,bok,bok);
  repeat
    gr:=gr div 2;
    bok:=bok div 2;
    for x:=0 to n-1 do
      for y:=0 to n-1 do
        bar(bok+2*x*bok-gr,bok+2*y*bok-gr,
            bok+2*x*bok+gr,bok+2*y*bok+gr);
    n:=n*2;
    readLn;
  until bok=1;
  CloseGraph;
end.