(0) Obligation:
Q restricted rewrite system:
The TRS R consists of the following rules:
a(x) → x
a(b(x)) → x
a(c(c(x))) → c(c(b(a(c(a(x))))))
Q is empty.
(1) QTRS Reverse (EQUIVALENT transformation)
We applied the QTRS Reverse Processor [REVERSE].
(2) Obligation:
Q restricted rewrite system:
The TRS R consists of the following rules:
a(x) → x
b(a(x)) → x
c(c(a(x))) → a(c(a(b(c(c(x))))))
Q is empty.
(3) DependencyPairsProof (EQUIVALENT transformation)
Using Dependency Pairs [AG00,LPAR04] we result in the following initial DP problem.
(4) Obligation:
Q DP problem:
The TRS P consists of the following rules:
C(c(a(x))) → A(c(a(b(c(c(x))))))
C(c(a(x))) → C(a(b(c(c(x)))))
C(c(a(x))) → A(b(c(c(x))))
C(c(a(x))) → B(c(c(x)))
C(c(a(x))) → C(c(x))
C(c(a(x))) → C(x)
The TRS R consists of the following rules:
a(x) → x
b(a(x)) → x
c(c(a(x))) → a(c(a(b(c(c(x))))))
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
(5) DependencyGraphProof (EQUIVALENT transformation)
The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 1 SCC with 3 less nodes.
(6) Obligation:
Q DP problem:
The TRS P consists of the following rules:
C(c(a(x))) → C(c(x))
C(c(a(x))) → C(a(b(c(c(x)))))
C(c(a(x))) → C(x)
The TRS R consists of the following rules:
a(x) → x
b(a(x)) → x
c(c(a(x))) → a(c(a(b(c(c(x))))))
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
(7) QDPOrderProof (EQUIVALENT transformation)
We use the reduction pair processor [LPAR04,JAR06].
The following pairs can be oriented strictly and are deleted.
C(c(a(x))) → C(x)
The remaining pairs can at least be oriented weakly.
Used ordering: Matrix interpretation [MATRO] with arctic natural numbers [ARCTIC]:
POL(c(x1)) = | | + | / | -I | 0A | 1A | \ |
| | -I | -I | 0A | | |
\ | 0A | 0A | 0A | / |
| · | x1 |
POL(a(x1)) = | | + | / | 1A | 1A | 1A | \ |
| | 0A | 0A | 0A | | |
\ | -I | 0A | 0A | / |
| · | x1 |
POL(b(x1)) = | | + | / | -I | 0A | -I | \ |
| | -I | 0A | -I | | |
\ | -I | 0A | -I | / |
| · | x1 |
The following usable rules [FROCOS05] with respect to the argument filtering of the ordering [JAR06] were oriented:
c(c(a(x))) → a(c(a(b(c(c(x))))))
b(a(x)) → x
a(x) → x
(8) Obligation:
Q DP problem:
The TRS P consists of the following rules:
C(c(a(x))) → C(c(x))
C(c(a(x))) → C(a(b(c(c(x)))))
The TRS R consists of the following rules:
a(x) → x
b(a(x)) → x
c(c(a(x))) → a(c(a(b(c(c(x))))))
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
(9) QDPOrderProof (EQUIVALENT transformation)
We use the reduction pair processor [LPAR04,JAR06].
The following pairs can be oriented strictly and are deleted.
C(c(a(x))) → C(a(b(c(c(x)))))
The remaining pairs can at least be oriented weakly.
Used ordering: Matrix interpretation [MATRO] with arctic natural numbers [ARCTIC]:
POL(c(x1)) = | | + | / | 0A | 1A | 0A | \ |
| | 0A | -I | 0A | | |
\ | -I | 0A | -I | / |
| · | x1 |
POL(a(x1)) = | | + | / | 1A | 0A | 1A | \ |
| | -I | 0A | 0A | | |
\ | 0A | 0A | 0A | / |
| · | x1 |
POL(b(x1)) = | | + | / | -I | -I | 0A | \ |
| | -I | -I | 0A | | |
\ | -I | -I | 0A | / |
| · | x1 |
The following usable rules [FROCOS05] with respect to the argument filtering of the ordering [JAR06] were oriented:
c(c(a(x))) → a(c(a(b(c(c(x))))))
b(a(x)) → x
a(x) → x
(10) Obligation:
Q DP problem:
The TRS P consists of the following rules:
C(c(a(x))) → C(c(x))
The TRS R consists of the following rules:
a(x) → x
b(a(x)) → x
c(c(a(x))) → a(c(a(b(c(c(x))))))
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
(11) QDPOrderProof (EQUIVALENT transformation)
We use the reduction pair processor [LPAR04,JAR06].
The following pairs can be oriented strictly and are deleted.
C(c(a(x))) → C(c(x))
The remaining pairs can at least be oriented weakly.
Used ordering: Matrix interpretation [MATRO] with arctic natural numbers [ARCTIC]:
POL(c(x1)) = | | + | / | 0A | 0A | 0A | \ |
| | 1A | -I | 0A | | |
\ | 0A | -I | 0A | / |
| · | x1 |
POL(a(x1)) = | | + | / | 0A | 0A | -I | \ |
| | 1A | 1A | 1A | | |
\ | 0A | 0A | 0A | / |
| · | x1 |
POL(b(x1)) = | | + | / | -I | -I | 0A | \ |
| | -I | -I | 0A | | |
\ | -I | -I | 0A | / |
| · | x1 |
The following usable rules [FROCOS05] with respect to the argument filtering of the ordering [JAR06] were oriented:
c(c(a(x))) → a(c(a(b(c(c(x))))))
b(a(x)) → x
a(x) → x
(12) Obligation:
Q DP problem:
P is empty.
The TRS R consists of the following rules:
a(x) → x
b(a(x)) → x
c(c(a(x))) → a(c(a(b(c(c(x))))))
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
(13) PisEmptyProof (EQUIVALENT transformation)
The TRS P is empty. Hence, there is no (P,Q,R) chain.
(14) YES