uses crt,graph; vardriver,mode:integer;
var a,b,x,y:integer;
n:integer;
procedure lerl (dx,dy:integer);
begin delay(5);
x:=x+dx;y:=y+dy; lineto(x,y);
end;
procedure bb(k:integer);forward;
procedure cc(k:integer);forward;
procedure dd(k:integer);forward;
procedure aa(k:integer);
begin
if K>0 then
begin
aa (k-1); lerl(a,b); setlinestyle(1,0,4); setbkcolor(15);
bb(k-1); lerl(a,0); ;
dd(k-1);lerl(a,-b);
aa(k-1);
end;
end;
procedure bb(k:integer);
begin
if K>0 then begin SETCOLOR(RANDOM(12));
bb(k-1); lerl(-a,b);
cc(k-1); lerl(0,b);
aa (k-1); lerl(a,b);
bb(k-1);
end;
end;
procedure cc(k:integer);
begin if k>0 then
begin
cc(k-1); lerl(-a,-b);
dd(k-1); lerl(-a,0);
bb (k-1); lerl(-a,b);
cc(k-1);
end;
end;
procedure dd(k:integer);
begin
if k>0 then
begin
dd(k-1); lerl(a,-b);
aa(k-1); lerl(0,-b);
cc (k-1); lerl(-a,-b);
dd(k-1);
end;
end;
begin driver:=detect; initgraph (driver,mode,'c:\bp\bgi');
n:=6;a:=3; b:=a; x:=10; y:=10;
moveto (x,y);
aa(n);setcolor(1); lerl(a,b);
bb(n); setcolor(12);lerl(-a,b);
cc (n);setcolor(14); lerl(-a,-b);
dd(n); lerl(a,-b);
end.