YES
Time: 0.010

Problem:
 Equations:
  
 TRS:
  fAC(x,one()) -> x
  fAC(x,x) -> x

Proof:
 AC-RPO Processor:
  precedence:
   one > fAC
  status:
   
  problem:
   Equations:
    
   TRS:
    
  Qed