Term Rewriting System R:
[y, x]
f(y, f(x, f(a, x))) -> f(f(a, f(x, a)), f(a, y))
f(x, f(x, y)) -> f(f(f(x, a), a), a)

Termination of R to be shown.



   R
Dependency Pair Analysis



R contains the following Dependency Pairs:

F(y, f(x, f(a, x))) -> F(f(a, f(x, a)), f(a, y))
F(y, f(x, f(a, x))) -> F(a, f(x, a))
F(y, f(x, f(a, x))) -> F(x, a)
F(y, f(x, f(a, x))) -> F(a, y)
F(x, f(x, y)) -> F(f(f(x, a), a), a)
F(x, f(x, y)) -> F(f(x, a), a)
F(x, f(x, y)) -> F(x, a)

Furthermore, R contains one SCC.


   R
DPs
       →DP Problem 1
Narrowing Transformation


Dependency Pairs:

F(y, f(x, f(a, x))) -> F(a, y)
F(y, f(x, f(a, x))) -> F(a, f(x, a))
F(y, f(x, f(a, x))) -> F(f(a, f(x, a)), f(a, y))


Rules:


f(y, f(x, f(a, x))) -> f(f(a, f(x, a)), f(a, y))
f(x, f(x, y)) -> f(f(f(x, a), a), a)





On this DP problem, a Narrowing SCC transformation can be performed.
As a result of transforming the rule

F(y, f(x, f(a, x))) -> F(a, f(x, a))
no new Dependency Pairs are created.
The transformation is resulting in one new DP problem:



   R
DPs
       →DP Problem 1
Nar
           →DP Problem 2
Remaining Obligation(s)




The following remains to be proven:
Dependency Pairs:

F(y, f(x, f(a, x))) -> F(f(a, f(x, a)), f(a, y))
F(y, f(x, f(a, x))) -> F(a, y)


Rules:


f(y, f(x, f(a, x))) -> f(f(a, f(x, a)), f(a, y))
f(x, f(x, y)) -> f(f(f(x, a), a), a)




Termination of R could not be shown.
Duration:
0:00 minutes