(0) Obligation:

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

b(a, f(b(b(z, y), a))) → z
c(c(z, x, a), a, y) → f(f(c(y, a, f(c(z, y, x)))))
f(f(c(a, y, z))) → b(y, b(z, z))

Q is empty.

(1) DependencyPairsProof (EQUIVALENT transformation)

Using Dependency Pairs [AG00,LPAR04] we result in the following initial DP problem.

(2) Obligation:

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

C(c(z, x, a), a, y) → F(f(c(y, a, f(c(z, y, x)))))
C(c(z, x, a), a, y) → F(c(y, a, f(c(z, y, x))))
C(c(z, x, a), a, y) → C(y, a, f(c(z, y, x)))
C(c(z, x, a), a, y) → F(c(z, y, x))
C(c(z, x, a), a, y) → C(z, y, x)
F(f(c(a, y, z))) → B(y, b(z, z))
F(f(c(a, y, z))) → B(z, z)

The TRS R consists of the following rules:

b(a, f(b(b(z, y), a))) → z
c(c(z, x, a), a, y) → f(f(c(y, a, f(c(z, y, x)))))
f(f(c(a, y, z))) → b(y, b(z, z))

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

(3) DependencyGraphProof (EQUIVALENT transformation)

The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 1 SCC with 5 less nodes.

(4) Obligation:

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

C(c(z, x, a), a, y) → C(z, y, x)
C(c(z, x, a), a, y) → C(y, a, f(c(z, y, x)))

The TRS R consists of the following rules:

b(a, f(b(b(z, y), a))) → z
c(c(z, x, a), a, y) → f(f(c(y, a, f(c(z, y, x)))))
f(f(c(a, y, z))) → b(y, b(z, z))

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

(5) QDPOrderProof (EQUIVALENT transformation)

We use the reduction pair processor [LPAR04].


The following pairs can be oriented strictly and are deleted.


C(c(z, x, a), a, y) → C(z, y, x)
The remaining pairs can at least be oriented weakly.
Used ordering: Matrix interpretation [MATRO] with arctic natural numbers [ARCTIC]:

POL(C(x1, x2, x3)) =
/-I\
|-I|
\-I/
+
/2A0A-I\
|-I-I-I|
\-I-I-I/
·x1 +
/-I-I-I\
|-I-I-I|
\-I-I-I/
·x2 +
/2A0A2A\
|-I-I-I|
\-I-I-I/
·x3

POL(c(x1, x2, x3)) =
/-I\
|-I|
\-I/
+
/2A0A0A\
|2A0A0A|
\2A0A-I/
·x1 +
/2A0A2A\
|0A-I0A|
\0A-I0A/
·x2 +
/2A0A2A\
|2A0A2A|
\2A0A2A/
·x3

POL(a) =
/0A\
|-I|
\0A/

POL(f(x1)) =
/0A\
|-I|
\-I/
+
/-I0A0A\
|0A0A0A|
\-I0A0A/
·x1

POL(b(x1, x2)) =
/-I\
|-I|
\0A/
+
/0A-I0A\
|2A0A0A|
\2A0A1A/
·x1 +
/0A0A0A\
|0A0A0A|
\0A0A0A/
·x2

The following usable rules [FROCOS05] were oriented:

c(c(z, x, a), a, y) → f(f(c(y, a, f(c(z, y, x)))))
f(f(c(a, y, z))) → b(y, b(z, z))
b(a, f(b(b(z, y), a))) → z

(6) Obligation:

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

C(c(z, x, a), a, y) → C(y, a, f(c(z, y, x)))

The TRS R consists of the following rules:

b(a, f(b(b(z, y), a))) → z
c(c(z, x, a), a, y) → f(f(c(y, a, f(c(z, y, x)))))
f(f(c(a, y, z))) → b(y, b(z, z))

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

(7) QDPOrderProof (EQUIVALENT transformation)

We use the reduction pair processor [LPAR04].


The following pairs can be oriented strictly and are deleted.


C(c(z, x, a), a, y) → C(y, a, f(c(z, y, x)))
The remaining pairs can at least be oriented weakly.
Used ordering: Matrix interpretation [MATRO] with arctic natural numbers [ARCTIC]:

POL(C(x1, x2, x3)) =
/-I\
|-I|
\-I/
+
/2A-I-I\
|-I-I-I|
\-I-I-I/
·x1 +
/-I-I-I\
|-I-I-I|
\-I-I-I/
·x2 +
/3A-I0A\
|-I-I-I|
\-I-I-I/
·x3

POL(c(x1, x2, x3)) =
/3A\
|0A|
\0A/
+
/2A-I0A\
|0A-I-I|
\0A-I0A/
·x1 +
/3A0A2A\
|-I-I-I|
\0A-I-I/
·x2 +
/2A-I0A\
|1A-I0A|
\2A-I0A/
·x3

POL(a) =
/0A\
|0A|
\0A/

POL(f(x1)) =
/1A\
|-I|
\0A/
+
/-I0A-I\
|0A-I0A|
\-I0A0A/
·x1

POL(b(x1, x2)) =
/-I\
|-I|
\1A/
+
/3A0A0A\
|0A-I-I|
\2A-I0A/
·x1 +
/-I0A0A\
|-I-I0A|
\-I-I0A/
·x2

The following usable rules [FROCOS05] were oriented:

c(c(z, x, a), a, y) → f(f(c(y, a, f(c(z, y, x)))))
f(f(c(a, y, z))) → b(y, b(z, z))
b(a, f(b(b(z, y), a))) → z

(8) Obligation:

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

b(a, f(b(b(z, y), a))) → z
c(c(z, x, a), a, y) → f(f(c(y, a, f(c(z, y, x)))))
f(f(c(a, y, z))) → b(y, b(z, z))

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

(9) PisEmptyProof (EQUIVALENT transformation)

The TRS P is empty. Hence, there is no (P,Q,R) chain.

(10) TRUE