EQUATIONS: 
f(f(x,y),z) = f(x,f(y,z))
f(a1(),y) = y
f(a2(),y) = y
f(x,i1(x)) = a1()
f(x,i2(x)) = a2()

COMPLETE TRS:
RULES:
f(f(x,y),z) -> f(x,f(y,z))
f(a2(),y) -> y
f(x,i1(x)) -> i1(a2())
f(i1(a2()),x) -> x
i1(i1(a2())) -> i1(a2())
f(x,i1(a2())) -> i1(i1(x))
f(i1(x),f(x,y)) -> y
i1(i1(i1(x))) -> i1(x)
f(i1(i1(x)),y) -> f(x,y)
a1() -> i1(a2())
f(y,f(i1(y),x)) -> x
i2(x) -> f(i1(x),a2())
i1(f(y,x)) -> f(i1(x),i1(y))

SUCCESS
MaxTRS: 2 
Search time: 0.95 seconds