YES
Time: 0.027

Problem:
 Equations:
  
 TRS:
  fAC(g(fAC(h(a()),a())),a()) -> fAC(h(a()),fAC(a(),a()))
  fAC(h(a()),g(a())) -> fAC(g(h(a())),a())
  fAC(g(h(a())),fAC(b(),fAC(b(),b()))) -> fAC(g(fAC(h(a()),a())),a())
  fAC(h(a()),a()) -> fAC(h(a()),b())

Proof:
 AC-KBO Processor:
  precedence:
   h > fAC > b ~ g ~ a
   weight function:
    w0 = 2
    w(a) = 12
    w(b) = w(g) = w(h) = 8
    w(fAC) = 0
   problem:
    Equations:
     
    TRS:
     
   Qed