(0) Obligation:
Q restricted rewrite system:
The TRS R consists of the following rules:
a(b(x)) → x
a(c(x)) → b(c(a(a(x))))
c(b(x)) → a(c(x))
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:
A(c(x)) → C(a(a(x)))
A(c(x)) → A(a(x))
A(c(x)) → A(x)
C(b(x)) → A(c(x))
C(b(x)) → C(x)
The TRS R consists of the following rules:
a(b(x)) → x
a(c(x)) → b(c(a(a(x))))
c(b(x)) → a(c(x))
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
 
(3) 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:
A(c(x)) → A(a(x))
A(c(x)) → A(x)
Used ordering: Polynomial interpretation [POLO]:
POL(A(x1)) = x1   
POL(C(x1)) = 2 + 2·x1   
POL(a(x1)) = x1   
POL(b(x1)) = x1   
POL(c(x1)) = 2 + 2·x1   
 
(4) Obligation:
Q DP problem:
The TRS P consists of the following rules:
A(c(x)) → C(a(a(x)))
C(b(x)) → A(c(x))
C(b(x)) → C(x)
The TRS R consists of the following rules:
a(b(x)) → x
a(c(x)) → b(c(a(a(x))))
c(b(x)) → a(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.
C(b(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)) =  |  |  +  | | / | 0A | 0A | -I | \ |  
| | | 0A | 0A | 1A | | |  
| \ | -I | -I | 0A | / |  
  | · | x1 | 
| POL(a(x1)) =  |  |  +  | | / | -I | 0A | 0A | \ |  
| | | -I | -I | 0A | | |  
| \ | -I | 0A | -I | / |  
  | · | x1 | 
| POL(b(x1)) =  |  |  +  | | / | 0A | 0A | 1A | \ |  
| | | -I | -I | 0A | | |  
| \ | 0A | 0A | 1A | / |  
  | · | x1 | 
The following usable rules [FROCOS05] with respect to the argument filtering of the ordering [JAR06] were oriented:
a(b(x)) → x
a(c(x)) → b(c(a(a(x))))
c(b(x)) → a(c(x))
 
(6) Obligation:
Q DP problem:
The TRS P consists of the following rules:
A(c(x)) → C(a(a(x)))
C(b(x)) → A(c(x))
The TRS R consists of the following rules:
a(b(x)) → x
a(c(x)) → b(c(a(a(x))))
c(b(x)) → a(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.
A(c(x)) → C(a(a(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 | 1A | \ |  
| | | -I | -I | -I | | |  
| \ | -I | 0A | 0A | / |  
  | · | x1 | 
| POL(a(x1)) =  |  |  +  | | / | -I | 0A | 0A | \ |  
| | | -I | 0A | -I | | |  
| \ | 0A | 0A | -I | / |  
  | · | x1 | 
| POL(b(x1)) =  |  |  +  | | / | -I | 0A | 0A | \ |  
| | | -I | 1A | -I | | |  
| \ | 0A | 0A | 1A | / |  
  | · | x1 | 
The following usable rules [FROCOS05] with respect to the argument filtering of the ordering [JAR06] were oriented:
a(b(x)) → x
a(c(x)) → b(c(a(a(x))))
c(b(x)) → a(c(x))
 
(8) Obligation:
Q DP problem:
The TRS P consists of the following rules:
C(b(x)) → A(c(x))
The TRS R consists of the following rules:
a(b(x)) → x
a(c(x)) → b(c(a(a(x))))
c(b(x)) → a(c(x))
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
 
(9) DependencyGraphProof (EQUIVALENT transformation)
The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 0 SCCs with 1 less node.
(10) TRUE