Problem:
 a() -> a()
 a() -> g(a())
 a() -> f(f(a(),a()),a())
 f(g(a()),f(a(),a())) -> f(g(a()),f(a(),a()))

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