uses graph, crt;
var d, m: integer;
    nurk, raadius: real;
begin
  d:=vga; m:=vgaMed;
  initgraph(d, m, '');
  nurk:=0;
  repeat
    putpixel(round(raadius*sin(nurk)), round(raadius*cos(nurk)), white);
    delay(50);
    cleardevice;
  until keypressed;
  closegraph;
end.