(0) Obligation:
Q restricted rewrite system:
The TRS R consists of the following rules:
a(c(x)) → c(b(c(c(a(x)))))
b(b(b(x))) → c(b(x))
d(d(x)) → d(b(d(b(d(x)))))
a(a(x)) → a(d(a(x)))
a(b(x)) → c(c(a(x)))
c(c(x)) → c(b(c(b(c(x)))))
c(c(c(x))) → c(b(b(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:
c(a(x)) → a(c(c(b(c(x)))))
b(b(b(x))) → b(c(x))
d(d(x)) → d(b(d(b(d(x)))))
a(a(x)) → a(d(a(x)))
b(a(x)) → a(c(c(x)))
c(c(x)) → c(b(c(b(c(x)))))
c(c(c(x))) → b(b(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(a(x)) → A(c(c(b(c(x)))))
C(a(x)) → C(c(b(c(x))))
C(a(x)) → C(b(c(x)))
C(a(x)) → B(c(x))
C(a(x)) → C(x)
B(b(b(x))) → B(c(x))
B(b(b(x))) → C(x)
D(d(x)) → D(b(d(b(d(x)))))
D(d(x)) → B(d(b(d(x))))
D(d(x)) → D(b(d(x)))
D(d(x)) → B(d(x))
A(a(x)) → A(d(a(x)))
A(a(x)) → D(a(x))
B(a(x)) → A(c(c(x)))
B(a(x)) → C(c(x))
B(a(x)) → C(x)
C(c(x)) → C(b(c(b(c(x)))))
C(c(x)) → B(c(b(c(x))))
C(c(x)) → C(b(c(x)))
C(c(x)) → B(c(x))
C(c(c(x))) → B(b(c(x)))
C(c(c(x))) → B(c(x))
The TRS R consists of the following rules:
c(a(x)) → a(c(c(b(c(x)))))
b(b(b(x))) → b(c(x))
d(d(x)) → d(b(d(b(d(x)))))
a(a(x)) → a(d(a(x)))
b(a(x)) → a(c(c(x)))
c(c(x)) → c(b(c(b(c(x)))))
c(c(c(x))) → b(b(c(x)))
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
 
(5) QDPOrderProof (EQUIVALENT transformation)
We use the reduction pair processor [LPAR04,JAR06].
The following pairs can be oriented strictly and are deleted.
D(d(x)) → D(b(d(b(d(x)))))
D(d(x)) → B(d(b(d(x))))
D(d(x)) → D(b(d(x)))
D(d(x)) → B(d(x))
The remaining pairs can at least be oriented weakly.
Used ordering:  Polynomial interpretation [POLO]:
POL(A(x1)) = 0   
POL(B(x1)) = 0   
POL(C(x1)) = 0   
POL(D(x1)) = x1   
POL(a(x1)) = 0   
POL(b(x1)) = 0   
POL(c(x1)) = 0   
POL(d(x1)) = 1   
The following usable rules [FROCOS05] with respect to the argument filtering of the ordering [JAR06] were oriented:
b(b(b(x))) → b(c(x))
b(a(x)) → a(c(c(x)))
a(a(x)) → a(d(a(x)))
 
(6) Obligation:
Q DP problem:
The TRS P consists of the following rules:
C(a(x)) → A(c(c(b(c(x)))))
C(a(x)) → C(c(b(c(x))))
C(a(x)) → C(b(c(x)))
C(a(x)) → B(c(x))
C(a(x)) → C(x)
B(b(b(x))) → B(c(x))
B(b(b(x))) → C(x)
A(a(x)) → A(d(a(x)))
A(a(x)) → D(a(x))
B(a(x)) → A(c(c(x)))
B(a(x)) → C(c(x))
B(a(x)) → C(x)
C(c(x)) → C(b(c(b(c(x)))))
C(c(x)) → B(c(b(c(x))))
C(c(x)) → C(b(c(x)))
C(c(x)) → B(c(x))
C(c(c(x))) → B(b(c(x)))
C(c(c(x))) → B(c(x))
The TRS R consists of the following rules:
c(a(x)) → a(c(c(b(c(x)))))
b(b(b(x))) → b(c(x))
d(d(x)) → d(b(d(b(d(x)))))
a(a(x)) → a(d(a(x)))
b(a(x)) → a(c(c(x)))
c(c(x)) → c(b(c(b(c(x)))))
c(c(c(x))) → b(b(c(x)))
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
 
(7) DependencyGraphProof (EQUIVALENT transformation)
The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 2 SCCs with 3 less nodes.
(8) Complex Obligation (AND)
(9) Obligation:
Q DP problem:
The TRS P consists of the following rules:
A(a(x)) → A(d(a(x)))
The TRS R consists of the following rules:
c(a(x)) → a(c(c(b(c(x)))))
b(b(b(x))) → b(c(x))
d(d(x)) → d(b(d(b(d(x)))))
a(a(x)) → a(d(a(x)))
b(a(x)) → a(c(c(x)))
c(c(x)) → c(b(c(b(c(x)))))
c(c(c(x))) → b(b(c(x)))
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
 
(10) QDPOrderProof (EQUIVALENT transformation)
We use the reduction pair processor [LPAR04,JAR06].
The following pairs can be oriented strictly and are deleted.
A(a(x)) → A(d(a(x)))
The remaining pairs can at least be oriented weakly.
Used ordering:  Polynomial Order [NEGPOLO,POLO] with Interpretation:
| POL( A(x1) ) = max{0, 2x1 - 2} | 
| POL( b(x1) ) = max{0, -2} | 
The following usable rules [FROCOS05] with respect to the argument filtering of the ordering [JAR06] were oriented:
d(d(x)) → d(b(d(b(d(x)))))
 
(11) Obligation:
Q DP problem:
P is empty.
The TRS R consists of the following rules:
c(a(x)) → a(c(c(b(c(x)))))
b(b(b(x))) → b(c(x))
d(d(x)) → d(b(d(b(d(x)))))
a(a(x)) → a(d(a(x)))
b(a(x)) → a(c(c(x)))
c(c(x)) → c(b(c(b(c(x)))))
c(c(c(x))) → b(b(c(x)))
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
 
(12) PisEmptyProof (EQUIVALENT transformation)
The TRS P is empty. Hence, there is no (P,Q,R) chain.
(13) YES
(14) Obligation:
Q DP problem:
The TRS P consists of the following rules:
C(a(x)) → C(b(c(x)))
C(a(x)) → C(c(b(c(x))))
C(a(x)) → B(c(x))
B(b(b(x))) → B(c(x))
B(b(b(x))) → C(x)
C(a(x)) → C(x)
C(c(x)) → C(b(c(b(c(x)))))
C(c(x)) → B(c(b(c(x))))
B(a(x)) → C(c(x))
C(c(x)) → C(b(c(x)))
C(c(x)) → B(c(x))
B(a(x)) → C(x)
C(c(c(x))) → B(b(c(x)))
C(c(c(x))) → B(c(x))
The TRS R consists of the following rules:
c(a(x)) → a(c(c(b(c(x)))))
b(b(b(x))) → b(c(x))
d(d(x)) → d(b(d(b(d(x)))))
a(a(x)) → a(d(a(x)))
b(a(x)) → a(c(c(x)))
c(c(x)) → c(b(c(b(c(x)))))
c(c(c(x))) → b(b(c(x)))
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
 
(15) QDPOrderProof (EQUIVALENT transformation)
We use the reduction pair processor [LPAR04,JAR06].
The following pairs can be oriented strictly and are deleted.
C(a(x)) → C(b(c(x)))
C(a(x)) → C(c(b(c(x))))
C(a(x)) → B(c(x))
C(a(x)) → C(x)
B(a(x)) → C(c(x))
B(a(x)) → C(x)
The remaining pairs can at least be oriented weakly.
Used ordering:  Polynomial interpretation [POLO]:
POL(B(x1)) = 1 + x1   
POL(C(x1)) = 1 + x1   
POL(a(x1)) = 1 + x1   
POL(b(x1)) = x1   
POL(c(x1)) = x1   
POL(d(x1)) = 0   
The following usable rules [FROCOS05] with respect to the argument filtering of the ordering [JAR06] were oriented:
c(a(x)) → a(c(c(b(c(x)))))
c(c(x)) → c(b(c(b(c(x)))))
c(c(c(x))) → b(b(c(x)))
b(b(b(x))) → b(c(x))
b(a(x)) → a(c(c(x)))
a(a(x)) → a(d(a(x)))
d(d(x)) → d(b(d(b(d(x)))))
 
(16) Obligation:
Q DP problem:
The TRS P consists of the following rules:
B(b(b(x))) → B(c(x))
B(b(b(x))) → C(x)
C(c(x)) → C(b(c(b(c(x)))))
C(c(x)) → B(c(b(c(x))))
C(c(x)) → C(b(c(x)))
C(c(x)) → B(c(x))
C(c(c(x))) → B(b(c(x)))
C(c(c(x))) → B(c(x))
The TRS R consists of the following rules:
c(a(x)) → a(c(c(b(c(x)))))
b(b(b(x))) → b(c(x))
d(d(x)) → d(b(d(b(d(x)))))
a(a(x)) → a(d(a(x)))
b(a(x)) → a(c(c(x)))
c(c(x)) → c(b(c(b(c(x)))))
c(c(c(x))) → b(b(c(x)))
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
 
(17) QDPOrderProof (EQUIVALENT transformation)
We use the reduction pair processor [LPAR04,JAR06].
The following pairs can be oriented strictly and are deleted.
B(b(b(x))) → C(x)
The remaining pairs can at least be oriented weakly.
Used ordering:  Matrix interpretation [MATRO] with arctic natural numbers [ARCTIC]:
| POL(b(x1)) =  |  |  +  | | / | -I | 0A | -I | \ |  
| | | -I | 0A | 0A | | |  
| \ | 0A | 1A | 0A | / |  
  | · | x1 | 
| POL(c(x1)) =  |  |  +  | | / | 1A | 0A | 0A | \ |  
| | | 0A | 0A | -I | | |  
| \ | 0A | 0A | -I | / |  
  | · | x1 | 
| POL(a(x1)) =  |  |  +  | | / | -I | -I | -I | \ |  
| | | -I | -I | -I | | |  
| \ | -I | -I | -I | / |  
  | · | x1 | 
| POL(d(x1)) =  |  |  +  | | / | 0A | -I | -I | \ |  
| | | 0A | -I | 0A | | |  
| \ | 0A | 0A | 0A | / |  
  | · | x1 | 
The following usable rules [FROCOS05] with respect to the argument filtering of the ordering [JAR06] were oriented:
c(a(x)) → a(c(c(b(c(x)))))
c(c(x)) → c(b(c(b(c(x)))))
c(c(c(x))) → b(b(c(x)))
b(b(b(x))) → b(c(x))
b(a(x)) → a(c(c(x)))
a(a(x)) → a(d(a(x)))
 
(18) Obligation:
Q DP problem:
The TRS P consists of the following rules:
B(b(b(x))) → B(c(x))
C(c(x)) → C(b(c(b(c(x)))))
C(c(x)) → B(c(b(c(x))))
C(c(x)) → C(b(c(x)))
C(c(x)) → B(c(x))
C(c(c(x))) → B(b(c(x)))
C(c(c(x))) → B(c(x))
The TRS R consists of the following rules:
c(a(x)) → a(c(c(b(c(x)))))
b(b(b(x))) → b(c(x))
d(d(x)) → d(b(d(b(d(x)))))
a(a(x)) → a(d(a(x)))
b(a(x)) → a(c(c(x)))
c(c(x)) → c(b(c(b(c(x)))))
c(c(c(x))) → b(b(c(x)))
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
 
(19) DependencyGraphProof (EQUIVALENT transformation)
The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 2 SCCs with 4 less nodes.
(20) Complex Obligation (AND)
(21) Obligation:
Q DP problem:
The TRS P consists of the following rules:
B(b(b(x))) → B(c(x))
The TRS R consists of the following rules:
c(a(x)) → a(c(c(b(c(x)))))
b(b(b(x))) → b(c(x))
d(d(x)) → d(b(d(b(d(x)))))
a(a(x)) → a(d(a(x)))
b(a(x)) → a(c(c(x)))
c(c(x)) → c(b(c(b(c(x)))))
c(c(c(x))) → b(b(c(x)))
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
 
(22) QDPOrderProof (EQUIVALENT transformation)
We use the reduction pair processor [LPAR04,JAR06].
The following pairs can be oriented strictly and are deleted.
B(b(b(x))) → B(c(x))
The remaining pairs can at least be oriented weakly.
Used ordering:  Matrix interpretation [MATRO] with arctic natural numbers [ARCTIC]:
| POL(b(x1)) =  |  |  +  | | / | -I | -I | 0A | \ |  
| | | -I | -I | 0A | | |  
| \ | 0A | 1A | 0A | / |  
  | · | x1 | 
| POL(c(x1)) =  |  |  +  | | / | -I | 0A | -I | \ |  
| | | 0A | 1A | -I | | |  
| \ | 0A | 0A | -I | / |  
  | · | x1 | 
| POL(a(x1)) =  |  |  +  | | / | -I | -I | -I | \ |  
| | | -I | -I | -I | | |  
| \ | -I | -I | -I | / |  
  | · | x1 | 
| POL(d(x1)) =  |  |  +  | | / | 0A | 0A | 0A | \ |  
| | | 0A | 1A | 1A | | |  
| \ | 0A | 0A | 0A | / |  
  | · | x1 | 
The following usable rules [FROCOS05] with respect to the argument filtering of the ordering [JAR06] were oriented:
c(a(x)) → a(c(c(b(c(x)))))
c(c(x)) → c(b(c(b(c(x)))))
c(c(c(x))) → b(b(c(x)))
b(b(b(x))) → b(c(x))
b(a(x)) → a(c(c(x)))
a(a(x)) → a(d(a(x)))
 
(23) Obligation:
Q DP problem:
P is empty.
The TRS R consists of the following rules:
c(a(x)) → a(c(c(b(c(x)))))
b(b(b(x))) → b(c(x))
d(d(x)) → d(b(d(b(d(x)))))
a(a(x)) → a(d(a(x)))
b(a(x)) → a(c(c(x)))
c(c(x)) → c(b(c(b(c(x)))))
c(c(c(x))) → b(b(c(x)))
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
 
(24) PisEmptyProof (EQUIVALENT transformation)
The TRS P is empty. Hence, there is no (P,Q,R) chain.
(25) YES
(26) Obligation:
Q DP problem:
The TRS P consists of the following rules:
C(c(x)) → C(b(c(x)))
C(c(x)) → C(b(c(b(c(x)))))
The TRS R consists of the following rules:
c(a(x)) → a(c(c(b(c(x)))))
b(b(b(x))) → b(c(x))
d(d(x)) → d(b(d(b(d(x)))))
a(a(x)) → a(d(a(x)))
b(a(x)) → a(c(c(x)))
c(c(x)) → c(b(c(b(c(x)))))
c(c(c(x))) → b(b(c(x)))
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
 
(27) QDPOrderProof (EQUIVALENT transformation)
We use the reduction pair processor [LPAR04,JAR06].
The following pairs can be oriented strictly and are deleted.
C(c(x)) → C(b(c(x)))
C(c(x)) → C(b(c(b(c(x)))))
The remaining pairs can at least be oriented weakly.
Used ordering:  Polynomial interpretation [POLO]:
POL(C(x1)) = x1   
POL(a(x1)) = 0   
POL(b(x1)) = 0   
POL(c(x1)) = 1   
POL(d(x1)) = 1 + x1   
The following usable rules [FROCOS05] with respect to the argument filtering of the ordering [JAR06] were oriented:
b(b(b(x))) → b(c(x))
b(a(x)) → a(c(c(x)))
a(a(x)) → a(d(a(x)))
 
(28) Obligation:
Q DP problem:
P is empty.
The TRS R consists of the following rules:
c(a(x)) → a(c(c(b(c(x)))))
b(b(b(x))) → b(c(x))
d(d(x)) → d(b(d(b(d(x)))))
a(a(x)) → a(d(a(x)))
b(a(x)) → a(c(c(x)))
c(c(x)) → c(b(c(b(c(x)))))
c(c(c(x))) → b(b(c(x)))
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
 
(29) PisEmptyProof (EQUIVALENT transformation)
The TRS P is empty. Hence, there is no (P,Q,R) chain.
(30) YES