MAYBE
Time: 0.001531
TRS:
 {f(f(s x, s y), f(z, w)) -> f(f(x, y), f(z, w)),
  f(f(s x, 0()), f(y, z)) -> f(f(y, z), f(y, s z))}
 DP:
  DP:
   {f#(f(s x, s y), f(z, w)) -> f#(x, y),
    f#(f(s x, s y), f(z, w)) -> f#(f(x, y), f(z, w)),
    f#(f(s x, 0()), f(y, z)) -> f#(y, s z),
    f#(f(s x, 0()), f(y, z)) -> f#(f(y, z), f(y, s z))}
  TRS:
  {f(f(s x, s y), f(z, w)) -> f(f(x, y), f(z, w)),
   f(f(s x, 0()), f(y, z)) -> f(f(y, z), f(y, s z))}
  EDG:
   {(f#(f(s x, s y), f(z, w)) -> f#(f(x, y), f(z, w)), f#(f(s x, 0()), f(y, z)) -> f#(f(y, z), f(y, s z)))
    (f#(f(s x, s y), f(z, w)) -> f#(f(x, y), f(z, w)), f#(f(s x, 0()), f(y, z)) -> f#(y, s z))
    (f#(f(s x, s y), f(z, w)) -> f#(f(x, y), f(z, w)), f#(f(s x, s y), f(z, w)) -> f#(f(x, y), f(z, w)))
    (f#(f(s x, s y), f(z, w)) -> f#(f(x, y), f(z, w)), f#(f(s x, s y), f(z, w)) -> f#(x, y))
    (f#(f(s x, s y), f(z, w)) -> f#(x, y), f#(f(s x, 0()), f(y, z)) -> f#(f(y, z), f(y, s z)))
    (f#(f(s x, s y), f(z, w)) -> f#(x, y), f#(f(s x, 0()), f(y, z)) -> f#(y, s z))
    (f#(f(s x, s y), f(z, w)) -> f#(x, y), f#(f(s x, s y), f(z, w)) -> f#(f(x, y), f(z, w)))
    (f#(f(s x, s y), f(z, w)) -> f#(x, y), f#(f(s x, s y), f(z, w)) -> f#(x, y))
    (f#(f(s x, 0()), f(y, z)) -> f#(f(y, z), f(y, s z)), f#(f(s x, s y), f(z, w)) -> f#(x, y))
    (f#(f(s x, 0()), f(y, z)) -> f#(f(y, z), f(y, s z)), f#(f(s x, s y), f(z, w)) -> f#(f(x, y), f(z, w)))
    (f#(f(s x, 0()), f(y, z)) -> f#(f(y, z), f(y, s z)), f#(f(s x, 0()), f(y, z)) -> f#(y, s z))
    (f#(f(s x, 0()), f(y, z)) -> f#(f(y, z), f(y, s z)), f#(f(s x, 0()), f(y, z)) -> f#(f(y, z), f(y, s z)))}
   STATUS:
    arrows: 0.250000
    SCCS (1):
     Scc:
      {f#(f(s x, s y), f(z, w)) -> f#(x, y),
       f#(f(s x, s y), f(z, w)) -> f#(f(x, y), f(z, w)),
       f#(f(s x, 0()), f(y, z)) -> f#(f(y, z), f(y, s z))}
     
     SCC (3):
      Strict:
       {f#(f(s x, s y), f(z, w)) -> f#(x, y),
        f#(f(s x, s y), f(z, w)) -> f#(f(x, y), f(z, w)),
        f#(f(s x, 0()), f(y, z)) -> f#(f(y, z), f(y, s z))}
      Weak:
      {f(f(s x, s y), f(z, w)) -> f(f(x, y), f(z, w)),
       f(f(s x, 0()), f(y, z)) -> f(f(y, z), f(y, s z))}
      Open