program dreieck; {Lutz Tautenhahn (c) 1995,1999}
uses dos,crt,graph;
const xmax=640;ymax=480;
      d: array [0..7] of integer = (60,65,71,78,85,93,101,110);
var zr, n:integer;
    zx0,zx1,zy0,zy1:real;
    x,y: array[0..2]of real;
    graphdriver,graphmode:integer;
    i:longint;

procedure ig;
begin
  graphdriver:=detect;
  initgraph(graphdriver,graphmode,'d:\tp\bgi');
end;

procedure xyinit;
begin
  x[0]:=320-5*d[n];y[0]:=480-8*d[n];
  x[1]:=320;y[1]:=480;
  x[2]:=320+5*d[n];y[2]:=480-8*d[n];
end;

begin
  n:=0;
  randomize;
  ig;
  repeat
    xyinit;
    zx0:=x[0];
    zy0:=y[0];
    setfillstyle(1,0);
    setcolor(0);
    bar(0,0,640,480);
    for i:=1 to 100000 do begin
      zr:=random(3);
      zx1:=(zx0+x[zr])/2;
      zy1:=(zy0+y[zr])/2;
      putpixel(round(zx1),round(zy1),15);
      zx0:=zx1;zy0:=zy1;
    end;
    sound(400);delay(10);nosound;
    n:=(n+1) mod 8;
  until keypressed;
  readln;
  closegraph;
end.