MAYBE
Time: 0.198

Problem:
 Equations:
  plusAC(plusAC(x2,x3),x4) -> plusAC(x2,plusAC(x3,x4))
  plusAC(x2,x3) -> plusAC(x3,x2)
  timesAC(timesAC(x2,x3),x4) -> timesAC(x2,timesAC(x3,x4))
  timesAC(x2,x3) -> timesAC(x3,x2)
  plusAC(x2,plusAC(x3,x4)) -> plusAC(plusAC(x2,x3),x4)
  plusAC(x3,x2) -> plusAC(x2,x3)
  timesAC(x2,timesAC(x3,x4)) -> timesAC(timesAC(x2,x3),x4)
  timesAC(x3,x2) -> timesAC(x2,x3)
 TRS:
  0(S()) -> S()
  plusAC(x,S()) -> x
  plusAC(0(x),0(y)) -> 0(plusAC(x,y))
  plusAC(0(x),1(y)) -> 1(plusAC(x,y))
  plusAC(1(x),1(y)) -> 0(1(plusAC(plusAC(x,y),S())))
  timesAC(x,S()) -> S()
  timesAC(x,0(y)) -> 0(timesAC(x,y))
  timesAC(x,1(y)) -> plusAC(x,0(timesAC(x,y)))

Proof:
 Open