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

Termination of R to be shown.



   R
Dependency Pair Analysis



R contains the following Dependency Pairs:

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

Furthermore, R contains one SCC.


   R
DPs
       →DP Problem 1
Modular Removal of Rules


Dependency Pairs:

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


Rules:


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





We have the following set of usable rules:

f(x, f(y, z)) -> f(f(x, y), z)
f(f(a, a), x) -> f(a, f(b, f(a, x)))
To remove rules and DPs from this DP problem we used the following monotonic and CE-compatible order: Polynomial ordering.
Polynomial interpretation:
  POL(b)=  0  
  POL(a)=  1  
  POL(F(x1, x2))=  1 + x1 + x2  
  POL(f(x1, x2))=  x1 + x2  

We have the following set D of usable symbols: {b, a, F, f}
The following Dependency Pairs can be deleted as the lhs is strictly greater than the corresponding rhs:

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

No Rules can be deleted.

The result of this processor delivers one new DP problem.



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




The following remains to be proven:
Dependency Pairs:

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


Rules:


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




Termination of R could not be shown.
Duration:
0:16 minutes