(0) Obligation:
Q restricted rewrite system:
The TRS R consists of the following rules:
r(e(x)) → w(r(x))
i(t(x)) → e(r(x))
e(w(x)) → r(i(x))
t(e(x)) → r(e(x))
w(r(x)) → i(t(x))
e(r(x)) → e(w(x))
r(i(t(e(r(x))))) → e(w(r(i(t(e(x))))))
Q is empty.
(1) QTRSRRRProof (EQUIVALENT transformation)
Used ordering:
Polynomial interpretation [POLO]:
POL(e(x1)) = 1 + x1
POL(i(x1)) = x1
POL(r(x1)) = 2 + x1
POL(t(x1)) = 3 + x1
POL(w(x1)) = 1 + x1
With this ordering the following rules can be removed by the rule removal processor [LPAR04] because they are oriented strictly:
t(e(x)) → r(e(x))
e(r(x)) → e(w(x))
(2) Obligation:
Q restricted rewrite system:
The TRS R consists of the following rules:
r(e(x)) → w(r(x))
i(t(x)) → e(r(x))
e(w(x)) → r(i(x))
w(r(x)) → i(t(x))
r(i(t(e(r(x))))) → e(w(r(i(t(e(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:
R(e(x)) → W(r(x))
R(e(x)) → R(x)
I(t(x)) → E(r(x))
I(t(x)) → R(x)
E(w(x)) → R(i(x))
E(w(x)) → I(x)
W(r(x)) → I(t(x))
R(i(t(e(r(x))))) → E(w(r(i(t(e(x))))))
R(i(t(e(r(x))))) → W(r(i(t(e(x)))))
R(i(t(e(r(x))))) → R(i(t(e(x))))
R(i(t(e(r(x))))) → I(t(e(x)))
R(i(t(e(r(x))))) → E(x)
The TRS R consists of the following rules:
r(e(x)) → w(r(x))
i(t(x)) → e(r(x))
e(w(x)) → r(i(x))
w(r(x)) → i(t(x))
r(i(t(e(r(x))))) → e(w(r(i(t(e(x))))))
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
(5) MRRProof (EQUIVALENT transformation)
By using the rule removal processor [LPAR04] with the following ordering, at least one Dependency Pair or term rewrite system rule of this QDP problem can be strictly oriented.
Strictly oriented dependency pairs:
R(e(x)) → R(x)
I(t(x)) → R(x)
E(w(x)) → I(x)
R(i(t(e(r(x))))) → W(r(i(t(e(x)))))
R(i(t(e(r(x))))) → R(i(t(e(x))))
R(i(t(e(r(x))))) → I(t(e(x)))
R(i(t(e(r(x))))) → E(x)
Used ordering: Polynomial interpretation [POLO]:
POL(E(x1)) = 1 + x1
POL(I(x1)) = x1
POL(R(x1)) = 2 + x1
POL(W(x1)) = 1 + x1
POL(e(x1)) = 1 + x1
POL(i(x1)) = x1
POL(r(x1)) = 2 + x1
POL(t(x1)) = 3 + x1
POL(w(x1)) = 1 + x1
(6) Obligation:
Q DP problem:
The TRS P consists of the following rules:
R(e(x)) → W(r(x))
I(t(x)) → E(r(x))
E(w(x)) → R(i(x))
W(r(x)) → I(t(x))
R(i(t(e(r(x))))) → E(w(r(i(t(e(x))))))
The TRS R consists of the following rules:
r(e(x)) → w(r(x))
i(t(x)) → e(r(x))
e(w(x)) → r(i(x))
w(r(x)) → i(t(x))
r(i(t(e(r(x))))) → e(w(r(i(t(e(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.
R(i(t(e(r(x))))) → E(w(r(i(t(e(x))))))
The remaining pairs can at least be oriented weakly.
Used ordering: Matrix interpretation [MATRO] with arctic natural numbers [ARCTIC]:
POL(e(x1)) = | | + | / | 0A | 0A | 0A | \ |
| | 0A | 0A | 0A | | |
\ | -I | -I | 0A | / |
| · | x1 |
POL(r(x1)) = | | + | / | 0A | -I | 0A | \ |
| | 0A | 0A | 0A | | |
\ | -I | -I | -I | / |
| · | x1 |
POL(t(x1)) = | | + | / | -I | 0A | 0A | \ |
| | -I | -I | -I | | |
\ | 0A | 0A | 0A | / |
| · | x1 |
POL(w(x1)) = | | + | / | 0A | 0A | 0A | \ |
| | 0A | 0A | 0A | | |
\ | -I | -I | 0A | / |
| · | x1 |
POL(i(x1)) = | | + | / | 0A | 0A | 0A | \ |
| | -I | -I | 0A | | |
\ | -I | 0A | -I | / |
| · | x1 |
The following usable rules [FROCOS05] with respect to the argument filtering of the ordering [JAR06] were oriented:
w(r(x)) → i(t(x))
i(t(x)) → e(r(x))
e(w(x)) → r(i(x))
r(e(x)) → w(r(x))
r(i(t(e(r(x))))) → e(w(r(i(t(e(x))))))
(8) Obligation:
Q DP problem:
The TRS P consists of the following rules:
R(e(x)) → W(r(x))
I(t(x)) → E(r(x))
E(w(x)) → R(i(x))
W(r(x)) → I(t(x))
The TRS R consists of the following rules:
r(e(x)) → w(r(x))
i(t(x)) → e(r(x))
e(w(x)) → r(i(x))
w(r(x)) → i(t(x))
r(i(t(e(r(x))))) → e(w(r(i(t(e(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.
R(e(x)) → W(r(x))
The remaining pairs can at least be oriented weakly.
Used ordering: Matrix interpretation [MATRO] with arctic natural numbers [ARCTIC]:
POL(e(x1)) = | | + | / | 0A | 0A | 1A | \ |
| | -I | 0A | 0A | | |
\ | -I | 0A | 0A | / |
| · | x1 |
POL(r(x1)) = | | + | / | 0A | 0A | 1A | \ |
| | -I | 0A | 0A | | |
\ | -I | 0A | 0A | / |
| · | x1 |
POL(t(x1)) = | | + | / | 0A | 0A | 1A | \ |
| | -I | 0A | 0A | | |
\ | 0A | 1A | 1A | / |
| · | x1 |
POL(w(x1)) = | | + | / | 0A | 0A | 1A | \ |
| | -I | 0A | 0A | | |
\ | -I | 0A | 0A | / |
| · | x1 |
POL(i(x1)) = | | + | / | -I | -I | 0A | \ |
| | -I | 0A | -I | | |
\ | -I | 0A | -I | / |
| · | x1 |
The following usable rules [FROCOS05] with respect to the argument filtering of the ordering [JAR06] were oriented:
w(r(x)) → i(t(x))
i(t(x)) → e(r(x))
e(w(x)) → r(i(x))
r(e(x)) → w(r(x))
r(i(t(e(r(x))))) → e(w(r(i(t(e(x))))))
(10) Obligation:
Q DP problem:
The TRS P consists of the following rules:
I(t(x)) → E(r(x))
E(w(x)) → R(i(x))
W(r(x)) → I(t(x))
The TRS R consists of the following rules:
r(e(x)) → w(r(x))
i(t(x)) → e(r(x))
e(w(x)) → r(i(x))
w(r(x)) → i(t(x))
r(i(t(e(r(x))))) → e(w(r(i(t(e(x))))))
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
(11) DependencyGraphProof (EQUIVALENT transformation)
The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 0 SCCs with 3 less nodes.
(12) TRUE