(0) Obligation:

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

f(X) → f(c)
cb

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:

f(x) → c'(f(x))
c'(x) → b'(x)

Q is empty.

(3) QTRS Reverse (EQUIVALENT transformation)

We applied the QTRS Reverse Processor [REVERSE].

(4) Obligation:

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

f(x) → c'(f(x))
c'(x) → b'(x)

Q is empty.

(5) AAECC Innermost (EQUIVALENT transformation)

We have applied [NOC,AAECCNOC] to switch to innermost. The TRS R 1 is

cb

The TRS R 2 is

f(X) → f(c)

The signature Sigma is {f}

(6) Obligation:

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

f(X) → f(c)
cb

The set Q consists of the following terms:

f(x0)
c

(7) DependencyPairsProof (EQUIVALENT transformation)

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

(8) Obligation:

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

F(X) → F(c)
F(X) → C

The TRS R consists of the following rules:

f(X) → f(c)
cb

The set Q consists of the following terms:

f(x0)
c

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

(9) DependencyGraphProof (EQUIVALENT transformation)

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

(10) Obligation:

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

F(X) → F(c)

The TRS R consists of the following rules:

f(X) → f(c)
cb

The set Q consists of the following terms:

f(x0)
c

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

(11) UsableRulesProof (EQUIVALENT transformation)

As all Q-normal forms are R-normal forms we are in the innermost case. Hence, by the usable rules processor [LPAR04] we can delete all non-usable rules [FROCOS05] from R.

(12) Obligation:

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

F(X) → F(c)

The TRS R consists of the following rules:

cb

The set Q consists of the following terms:

f(x0)
c

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

(13) QReductionProof (EQUIVALENT transformation)

We deleted the following terms from Q as each root-symbol of these terms does neither occur in P nor in R.[THIEMANN].

f(x0)

(14) Obligation:

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

F(X) → F(c)

The TRS R consists of the following rules:

cb

The set Q consists of the following terms:

c

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

(15) UsableRulesProof (EQUIVALENT transformation)

As all Q-normal forms are R-normal forms we are in the innermost case. Hence, by the usable rules processor [LPAR04] we can delete all non-usable rules [FROCOS05] from R.

(16) Obligation:

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

F(X) → F(c)

The TRS R consists of the following rules:

cb

The set Q consists of the following terms:

f(x0)
c

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

(17) QReductionProof (EQUIVALENT transformation)

We deleted the following terms from Q as each root-symbol of these terms does neither occur in P nor in R.[THIEMANN].

f(x0)

(18) Obligation:

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

F(X) → F(c)

The TRS R consists of the following rules:

cb

The set Q consists of the following terms:

c

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

(19) MNOCProof (EQUIVALENT transformation)

We use the modular non-overlap check [FROCOS05] to decrease Q to the empty set.

(20) Obligation:

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

F(X) → F(c)

The TRS R consists of the following rules:

cb

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

(21) NonTerminationProof (EQUIVALENT transformation)

We used the non-termination processor [FROCOS05] to show that the DP problem is infinite.
Found a loop by semiunifying a rule from P directly.

s = F(X) evaluates to t =F(c)

Thus s starts an infinite chain as s semiunifies with t with the following substitutions:
  • Semiunifier: [ ]
  • Matcher: [X / c]




Rewriting sequence

The DP semiunifies directly so there is only one rewrite step from F(X) to F(c).



(22) FALSE