Termination w.r.t. Q of the following Term Rewriting System could not be shown:

Q restricted rewrite system:
The TRS R consists of the following rules:

f2(a, x) -> f2(b, f2(c, x))
f2(a, f2(b, x)) -> f2(b, f2(a, x))
f2(d, f2(c, x)) -> f2(d, f2(a, x))
f2(a, f2(c, x)) -> f2(c, f2(a, x))

Q is empty.


QTRS
  ↳ DependencyPairsProof

Q restricted rewrite system:
The TRS R consists of the following rules:

f2(a, x) -> f2(b, f2(c, x))
f2(a, f2(b, x)) -> f2(b, f2(a, x))
f2(d, f2(c, x)) -> f2(d, f2(a, x))
f2(a, f2(c, x)) -> f2(c, f2(a, x))

Q is empty.

Using Dependency Pairs [1,13] we result in the following initial DP problem:
Q DP problem:
The TRS P consists of the following rules:

F2(a, f2(c, x)) -> F2(c, f2(a, x))
F2(a, x) -> F2(b, f2(c, x))
F2(d, f2(c, x)) -> F2(d, f2(a, x))
F2(a, x) -> F2(c, x)
F2(a, f2(b, x)) -> F2(a, x)
F2(a, f2(b, x)) -> F2(b, f2(a, x))
F2(a, f2(c, x)) -> F2(a, x)
F2(d, f2(c, x)) -> F2(a, x)

The TRS R consists of the following rules:

f2(a, x) -> f2(b, f2(c, x))
f2(a, f2(b, x)) -> f2(b, f2(a, x))
f2(d, f2(c, x)) -> f2(d, f2(a, x))
f2(a, f2(c, x)) -> f2(c, f2(a, x))

Q is empty.
We have to consider all minimal (P,Q,R)-chains.

↳ QTRS
  ↳ DependencyPairsProof
QDP
      ↳ DependencyGraphProof

Q DP problem:
The TRS P consists of the following rules:

F2(a, f2(c, x)) -> F2(c, f2(a, x))
F2(a, x) -> F2(b, f2(c, x))
F2(d, f2(c, x)) -> F2(d, f2(a, x))
F2(a, x) -> F2(c, x)
F2(a, f2(b, x)) -> F2(a, x)
F2(a, f2(b, x)) -> F2(b, f2(a, x))
F2(a, f2(c, x)) -> F2(a, x)
F2(d, f2(c, x)) -> F2(a, x)

The TRS R consists of the following rules:

f2(a, x) -> f2(b, f2(c, x))
f2(a, f2(b, x)) -> f2(b, f2(a, x))
f2(d, f2(c, x)) -> f2(d, f2(a, x))
f2(a, f2(c, x)) -> f2(c, f2(a, x))

Q is empty.
We have to consider all minimal (P,Q,R)-chains.
The approximation of the Dependency Graph [13,14,18] contains 2 SCCs with 5 less nodes.

↳ QTRS
  ↳ DependencyPairsProof
    ↳ QDP
      ↳ DependencyGraphProof
        ↳ AND
QDP
            ↳ QDPOrderProof
          ↳ QDP

Q DP problem:
The TRS P consists of the following rules:

F2(a, f2(b, x)) -> F2(a, x)
F2(a, f2(c, x)) -> F2(a, x)

The TRS R consists of the following rules:

f2(a, x) -> f2(b, f2(c, x))
f2(a, f2(b, x)) -> f2(b, f2(a, x))
f2(d, f2(c, x)) -> f2(d, f2(a, x))
f2(a, f2(c, x)) -> f2(c, f2(a, x))

Q is empty.
We have to consider all minimal (P,Q,R)-chains.
We use the reduction pair processor [13].


The following pairs can be oriented strictly and are deleted.


F2(a, f2(b, x)) -> F2(a, x)
F2(a, f2(c, x)) -> F2(a, x)
The remaining pairs can at least be oriented weakly.
none
Used ordering: Polynomial interpretation [21]:

POL(F2(x1, x2)) = x2   
POL(a) = 0   
POL(b) = 1   
POL(c) = 0   
POL(f2(x1, x2)) = 1 + x1 + x2   

The following usable rules [14] were oriented: none



↳ QTRS
  ↳ DependencyPairsProof
    ↳ QDP
      ↳ DependencyGraphProof
        ↳ AND
          ↳ QDP
            ↳ QDPOrderProof
QDP
                ↳ PisEmptyProof
          ↳ QDP

Q DP problem:
P is empty.
The TRS R consists of the following rules:

f2(a, x) -> f2(b, f2(c, x))
f2(a, f2(b, x)) -> f2(b, f2(a, x))
f2(d, f2(c, x)) -> f2(d, f2(a, x))
f2(a, f2(c, x)) -> f2(c, f2(a, x))

Q is empty.
We have to consider all minimal (P,Q,R)-chains.
The TRS P is empty. Hence, there is no (P,Q,R) chain.

↳ QTRS
  ↳ DependencyPairsProof
    ↳ QDP
      ↳ DependencyGraphProof
        ↳ AND
          ↳ QDP
QDP

Q DP problem:
The TRS P consists of the following rules:

F2(d, f2(c, x)) -> F2(d, f2(a, x))

The TRS R consists of the following rules:

f2(a, x) -> f2(b, f2(c, x))
f2(a, f2(b, x)) -> f2(b, f2(a, x))
f2(d, f2(c, x)) -> f2(d, f2(a, x))
f2(a, f2(c, x)) -> f2(c, f2(a, x))

Q is empty.
We have to consider all minimal (P,Q,R)-chains.