YES
Time: 0.001350
TRS:
 {f(f(a(), a()), x) -> f(x, f(a(), f(a(), a())))}
 DP:
  DP:
   {f#(f(a(), a()), x) -> f#(x, f(a(), f(a(), a()))),
    f#(f(a(), a()), x) -> f#(a(), f(a(), a()))}
  TRS:
  {f(f(a(), a()), x) -> f(x, f(a(), f(a(), a())))}
  EDG:
   {}
   STATUS:
    arrows: 1.000000
    SCCS (0):