Problem:
 a() -> a()
 a() -> g(a())
 g(g(b())) -> a()
 g(g(b())) -> b()

Proof:
 Uncurry Processor:
  a() -> a()
  a() -> f3(g(),a())
  f3(g(),f3(g(),b())) -> a()
  f3(g(),f3(g(),b())) -> b()
  Ground Confluence Processor:
   UN by decision procedure.