Problem:
 b() -> a()
 b() -> c()
 c() -> h(b())
 c() -> d()
 a() -> h(a())
 d() -> h(d())

Proof:
 Nonconfluence Processor:
  terms: h(a()) *<- b() ->* d()
  Qed
  
  first automaton:
   final states: {4}
   transitions:
    h(5) -> 5,4
    a() -> 5*
  
  second automaton:
   final states: {1}
   transitions:
    h(1) -> 1*
    d() -> 1*