(SIG
   (a   -> o)
   (b   -> o)
   (c   -> o)
   (e   -> o)
   (d   -> o)
   (g   o -> o)
   (h   o -> o)
)
(RULES
   a -> b
   a -> c
   a -> e
   b -> d
   c -> a
   d -> a
   d -> e
   g(x) -> h(a)
   h(x) -> e
)