YES
Time: 0.002645
TRS:
 {f(x, f(a(), a())) -> f(f(f(f(a(), a()), a()), a()), x)}
 DP:
  DP:
   {f#(x, f(a(), a())) -> f#(f(f(f(a(), a()), a()), a()), x),
    f#(x, f(a(), a())) -> f#(f(f(a(), a()), a()), a()),
    f#(x, f(a(), a())) -> f#(f(a(), a()), a())}
  TRS:
  {f(x, f(a(), a())) -> f(f(f(f(a(), a()), a()), a()), x)}
  UR:
   {}
   EDG:
    {}
    STATUS:
     arrows: 1.000000
     SCCS (0):