Problem:
 b() -> h(h(b(),a()),h(c(),b()))
 a() -> b()
 b() -> a()
 f(f(b())) -> a()

Proof:
 Uncurry Processor:
  b() -> f5(f5(h(),f5(f5(h(),b()),a())),f5(f5(h(),c()),b()))
  a() -> b()
  b() -> a()
  f5(f(),f5(f(),b())) -> a()
  Ground Confluence Processor:
   UN by decision procedure.