cls 255
colour 0
circle fill 50 5 4
line 50 5 50 12
draw 52 14
draw 55,16
draw 60 17
assign a 59
assign b 17
assign c -20
assign d -20
loop 4
  colour white
  markx c d 2
  inc c 2
  inc d
  markx c d 2
  colour yellow
  spray a b 10 3
  colour red
  spray a b 10 3
  colour orange
  markx a b 2
  assign c a
  assign d b
  dup frame
  dec b 2
  dec a 3
endloop
inc a
inc a
assign c 3
loop 4
  colour yellow
  circle fill a b c
  colour orange
  inc c
  spray a b c
  colour red
  inc c
  spray a b c
  dup frame
endloop
assign c 1
loop 10
  colour white
  circle fill a b c
  inc c 2
  colour orange
  circle a b c
  dup frame
endloop
colour white
circle a b c