EQUATIONS: 
f(x,f(y,z)) = f(f(x,y),z)
f(x,i(x)) = e()
f(e(),x) = x

COMPLETE TRS:
RULES:
f(x,i(x)) -> e()
f(e(),x) -> x
f(x,e()) -> i(i(x))
f(i(x),f(x,y)) -> y
i(i(i(x))) -> i(x)
f(f(x,y),z) -> f(x,f(y,z))
i(e()) -> e()
f(y,f(i(y),x)) -> x
f(i(i(x)),y) -> f(x,y)
i(f(y,x)) -> f(i(x),i(y))

SUCCESS
MaxTRS: 3 
Search time: 2.89 seconds