type
u=^uzl;
uzl=record
i:integer;
l,r:u;
end;
var h:u; n:integer;
 
procedure ShowTree(h:u; x,y,w,f:integer);
const a=5;
var s:string;
begin
  if h<>nil then begin
  ShowTree(h^.l, x-w div 4, y+4*a, w div 2, 1);
  with form1.Canvas do begin
    brush.Color:=clblack;
    if f<>0 then
    begin
     moveto(x,y);
     lineto(x+f*(w div 2), y-4*a);
    end;
    ellipse(x-a,y+a,x+a,y-a);
    str(h^.i,s);
    brush.style:=bsClear;
    font.Name:='tahoma';
    font.Size:=10;
    textout(x,y,s);
  end;
  showtree(h^.r, x+w div 4, y+4*a, w div 2, -1);
  end;
end;
 
procedure TForm1.Button1Click(Sender: TObject);
function tree(k:integer):u;
var t:u;
begin
  if (k=0) then begin
  tree:=nil; exit; end;
  new(t);
  t^.i:=random(100);
  t^.l:=tree(k div 2);
  t^.r:=tree(k-(k div 2)-1);
  tree:=t;
end;
begin
n:=StrToInt(LabeledEdit1.Text);
h:=tree(n);
ShowTree(h,320,50,460,0);
end;