TIMEOUT
MAYBE
Trs:
 {    f mark -> f,
    f active -> f,
      c mark -> c,
    c active -> c,
      g mark -> g,
    g active -> g,
      d mark -> d,
    d active -> d,
      mark f -> active f mark,
      mark c -> active c,
      mark g -> active g,
      mark d -> active d,
      mark h -> active h mark,
  active f f -> mark c f g f,
    active c -> mark d,
    active h -> mark c d,
      h mark -> h,
    h active -> h}
 Open