Termination w.r.t. Q of the following Term Rewriting System could be disproven:

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

incr(nil) → nil
incr(cons(X, L)) → cons(s(X), incr(L))
adx(nil) → nil
adx(cons(X, L)) → incr(cons(X, adx(L)))
natsadx(zeros)
zeroscons(0, zeros)
head(cons(X, L)) → X
tail(cons(X, L)) → L

The set Q consists of the following terms:

adx(nil)
tail(cons(x0, x1))
zeros
adx(cons(x0, x1))
incr(nil)
head(cons(x0, x1))
nats
incr(cons(x0, x1))



QTRS
  ↳ RRRPoloQTRSProof

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

incr(nil) → nil
incr(cons(X, L)) → cons(s(X), incr(L))
adx(nil) → nil
adx(cons(X, L)) → incr(cons(X, adx(L)))
natsadx(zeros)
zeroscons(0, zeros)
head(cons(X, L)) → X
tail(cons(X, L)) → L

The set Q consists of the following terms:

adx(nil)
tail(cons(x0, x1))
zeros
adx(cons(x0, x1))
incr(nil)
head(cons(x0, x1))
nats
incr(cons(x0, x1))


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

incr(nil) → nil
incr(cons(X, L)) → cons(s(X), incr(L))
adx(nil) → nil
adx(cons(X, L)) → incr(cons(X, adx(L)))
natsadx(zeros)
zeroscons(0, zeros)
head(cons(X, L)) → X
tail(cons(X, L)) → L

The set Q consists of the following terms:

adx(nil)
tail(cons(x0, x1))
zeros
adx(cons(x0, x1))
incr(nil)
head(cons(x0, x1))
nats
incr(cons(x0, x1))

The following rules can be removed by the rule removal processor [15] because they are oriented strictly by a polynomial ordering:

adx(nil) → nil
head(cons(X, L)) → X
tail(cons(X, L)) → L
Used ordering:
Polynomial interpretation [25]:

POL(0) = 0   
POL(adx(x1)) = 2·x1   
POL(cons(x1, x2)) = 2·x1 + x2   
POL(head(x1)) = 2 + x1   
POL(incr(x1)) = x1   
POL(nats) = 0   
POL(nil) = 2   
POL(s(x1)) = x1   
POL(tail(x1)) = 2 + x1   
POL(zeros) = 0   




↳ QTRS
  ↳ RRRPoloQTRSProof
QTRS
      ↳ RRRPoloQTRSProof

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

incr(nil) → nil
incr(cons(X, L)) → cons(s(X), incr(L))
adx(cons(X, L)) → incr(cons(X, adx(L)))
natsadx(zeros)
zeroscons(0, zeros)

The set Q consists of the following terms:

adx(nil)
tail(cons(x0, x1))
zeros
adx(cons(x0, x1))
incr(nil)
head(cons(x0, x1))
nats
incr(cons(x0, x1))


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

incr(nil) → nil
incr(cons(X, L)) → cons(s(X), incr(L))
adx(cons(X, L)) → incr(cons(X, adx(L)))
natsadx(zeros)
zeroscons(0, zeros)

The set Q consists of the following terms:

adx(nil)
tail(cons(x0, x1))
zeros
adx(cons(x0, x1))
incr(nil)
head(cons(x0, x1))
nats
incr(cons(x0, x1))

The following rules can be removed by the rule removal processor [15] because they are oriented strictly by a polynomial ordering:

natsadx(zeros)
Used ordering:
Polynomial interpretation [25]:

POL(0) = 0   
POL(adx(x1)) = 2·x1   
POL(cons(x1, x2)) = 2·x1 + 2·x2   
POL(incr(x1)) = x1   
POL(nats) = 2   
POL(nil) = 0   
POL(s(x1)) = x1   
POL(zeros) = 0   




↳ QTRS
  ↳ RRRPoloQTRSProof
    ↳ QTRS
      ↳ RRRPoloQTRSProof
QTRS
          ↳ DependencyPairsProof

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

incr(nil) → nil
incr(cons(X, L)) → cons(s(X), incr(L))
adx(cons(X, L)) → incr(cons(X, adx(L)))
zeroscons(0, zeros)

The set Q consists of the following terms:

adx(nil)
tail(cons(x0, x1))
zeros
adx(cons(x0, x1))
incr(nil)
head(cons(x0, x1))
nats
incr(cons(x0, x1))


Using Dependency Pairs [1,15] we result in the following initial DP problem:
Q DP problem:
The TRS P consists of the following rules:

ZEROSZEROS
ADX(cons(X, L)) → ADX(L)
ADX(cons(X, L)) → INCR(cons(X, adx(L)))
INCR(cons(X, L)) → INCR(L)

The TRS R consists of the following rules:

incr(nil) → nil
incr(cons(X, L)) → cons(s(X), incr(L))
adx(cons(X, L)) → incr(cons(X, adx(L)))
zeroscons(0, zeros)

The set Q consists of the following terms:

adx(nil)
tail(cons(x0, x1))
zeros
adx(cons(x0, x1))
incr(nil)
head(cons(x0, x1))
nats
incr(cons(x0, x1))

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

↳ QTRS
  ↳ RRRPoloQTRSProof
    ↳ QTRS
      ↳ RRRPoloQTRSProof
        ↳ QTRS
          ↳ DependencyPairsProof
QDP
              ↳ DependencyGraphProof

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

ZEROSZEROS
ADX(cons(X, L)) → ADX(L)
ADX(cons(X, L)) → INCR(cons(X, adx(L)))
INCR(cons(X, L)) → INCR(L)

The TRS R consists of the following rules:

incr(nil) → nil
incr(cons(X, L)) → cons(s(X), incr(L))
adx(cons(X, L)) → incr(cons(X, adx(L)))
zeroscons(0, zeros)

The set Q consists of the following terms:

adx(nil)
tail(cons(x0, x1))
zeros
adx(cons(x0, x1))
incr(nil)
head(cons(x0, x1))
nats
incr(cons(x0, x1))

We have to consider all minimal (P,Q,R)-chains.
The approximation of the Dependency Graph [15,17,22] contains 3 SCCs with 1 less node.

↳ QTRS
  ↳ RRRPoloQTRSProof
    ↳ QTRS
      ↳ RRRPoloQTRSProof
        ↳ QTRS
          ↳ DependencyPairsProof
            ↳ QDP
              ↳ DependencyGraphProof
                ↳ AND
QDP
                    ↳ UsableRulesProof
                  ↳ QDP
                  ↳ QDP

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

ZEROSZEROS

The TRS R consists of the following rules:

incr(nil) → nil
incr(cons(X, L)) → cons(s(X), incr(L))
adx(cons(X, L)) → incr(cons(X, adx(L)))
zeroscons(0, zeros)

The set Q consists of the following terms:

adx(nil)
tail(cons(x0, x1))
zeros
adx(cons(x0, x1))
incr(nil)
head(cons(x0, x1))
nats
incr(cons(x0, x1))

We have to consider all minimal (P,Q,R)-chains.
As all Q-normal forms are R-normal forms we are in the innermost case. Hence, by the usable rules processor [15] we can delete all non-usable rules [17] from R.

↳ QTRS
  ↳ RRRPoloQTRSProof
    ↳ QTRS
      ↳ RRRPoloQTRSProof
        ↳ QTRS
          ↳ DependencyPairsProof
            ↳ QDP
              ↳ DependencyGraphProof
                ↳ AND
                  ↳ QDP
                    ↳ UsableRulesProof
QDP
                        ↳ QReductionProof
                  ↳ QDP
                  ↳ QDP

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

ZEROSZEROS

R is empty.
The set Q consists of the following terms:

adx(nil)
tail(cons(x0, x1))
zeros
adx(cons(x0, x1))
incr(nil)
head(cons(x0, x1))
nats
incr(cons(x0, x1))

We have to consider all minimal (P,Q,R)-chains.
We deleted the following terms from Q as each root-symbol of these terms does neither occur in P nor in R.

adx(nil)
tail(cons(x0, x1))
zeros
adx(cons(x0, x1))
incr(nil)
head(cons(x0, x1))
nats
incr(cons(x0, x1))



↳ QTRS
  ↳ RRRPoloQTRSProof
    ↳ QTRS
      ↳ RRRPoloQTRSProof
        ↳ QTRS
          ↳ DependencyPairsProof
            ↳ QDP
              ↳ DependencyGraphProof
                ↳ AND
                  ↳ QDP
                    ↳ UsableRulesProof
                      ↳ QDP
                        ↳ QReductionProof
QDP
                            ↳ NonTerminationProof
                  ↳ QDP
                  ↳ QDP

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

ZEROSZEROS

R is empty.
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
We used the non-termination processor [17] to show that the DP problem is infinite.
Found a loop by semiunifying a rule from P directly.

The TRS P consists of the following rules:

ZEROSZEROS

The TRS R consists of the following rules:none


s = ZEROS evaluates to t =ZEROS

Thus s starts an infinite chain as s semiunifies with t with the following substitutions:




Rewriting sequence

The DP semiunifies directly so there is only one rewrite step from ZEROS to ZEROS.





↳ QTRS
  ↳ RRRPoloQTRSProof
    ↳ QTRS
      ↳ RRRPoloQTRSProof
        ↳ QTRS
          ↳ DependencyPairsProof
            ↳ QDP
              ↳ DependencyGraphProof
                ↳ AND
                  ↳ QDP
QDP
                    ↳ UsableRulesProof
                  ↳ QDP

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

INCR(cons(X, L)) → INCR(L)

The TRS R consists of the following rules:

incr(nil) → nil
incr(cons(X, L)) → cons(s(X), incr(L))
adx(cons(X, L)) → incr(cons(X, adx(L)))
zeroscons(0, zeros)

The set Q consists of the following terms:

adx(nil)
tail(cons(x0, x1))
zeros
adx(cons(x0, x1))
incr(nil)
head(cons(x0, x1))
nats
incr(cons(x0, x1))

We have to consider all minimal (P,Q,R)-chains.
As all Q-normal forms are R-normal forms we are in the innermost case. Hence, by the usable rules processor [15] we can delete all non-usable rules [17] from R.

↳ QTRS
  ↳ RRRPoloQTRSProof
    ↳ QTRS
      ↳ RRRPoloQTRSProof
        ↳ QTRS
          ↳ DependencyPairsProof
            ↳ QDP
              ↳ DependencyGraphProof
                ↳ AND
                  ↳ QDP
                  ↳ QDP
                    ↳ UsableRulesProof
QDP
                        ↳ QReductionProof
                  ↳ QDP

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

INCR(cons(X, L)) → INCR(L)

R is empty.
The set Q consists of the following terms:

adx(nil)
tail(cons(x0, x1))
zeros
adx(cons(x0, x1))
incr(nil)
head(cons(x0, x1))
nats
incr(cons(x0, x1))

We have to consider all minimal (P,Q,R)-chains.
We deleted the following terms from Q as each root-symbol of these terms does neither occur in P nor in R.

adx(nil)
tail(cons(x0, x1))
zeros
adx(cons(x0, x1))
incr(nil)
head(cons(x0, x1))
nats
incr(cons(x0, x1))



↳ QTRS
  ↳ RRRPoloQTRSProof
    ↳ QTRS
      ↳ RRRPoloQTRSProof
        ↳ QTRS
          ↳ DependencyPairsProof
            ↳ QDP
              ↳ DependencyGraphProof
                ↳ AND
                  ↳ QDP
                  ↳ QDP
                    ↳ UsableRulesProof
                      ↳ QDP
                        ↳ QReductionProof
QDP
                            ↳ QDPSizeChangeProof
                  ↳ QDP

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

INCR(cons(X, L)) → INCR(L)

R is empty.
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
By using the subterm criterion [20] together with the size-change analysis [32] we have proven that there are no infinite chains for this DP problem.

From the DPs we obtained the following set of size-change graphs:



↳ QTRS
  ↳ RRRPoloQTRSProof
    ↳ QTRS
      ↳ RRRPoloQTRSProof
        ↳ QTRS
          ↳ DependencyPairsProof
            ↳ QDP
              ↳ DependencyGraphProof
                ↳ AND
                  ↳ QDP
                  ↳ QDP
QDP
                    ↳ UsableRulesProof

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

ADX(cons(X, L)) → ADX(L)

The TRS R consists of the following rules:

incr(nil) → nil
incr(cons(X, L)) → cons(s(X), incr(L))
adx(cons(X, L)) → incr(cons(X, adx(L)))
zeroscons(0, zeros)

The set Q consists of the following terms:

adx(nil)
tail(cons(x0, x1))
zeros
adx(cons(x0, x1))
incr(nil)
head(cons(x0, x1))
nats
incr(cons(x0, x1))

We have to consider all minimal (P,Q,R)-chains.
As all Q-normal forms are R-normal forms we are in the innermost case. Hence, by the usable rules processor [15] we can delete all non-usable rules [17] from R.

↳ QTRS
  ↳ RRRPoloQTRSProof
    ↳ QTRS
      ↳ RRRPoloQTRSProof
        ↳ QTRS
          ↳ DependencyPairsProof
            ↳ QDP
              ↳ DependencyGraphProof
                ↳ AND
                  ↳ QDP
                  ↳ QDP
                  ↳ QDP
                    ↳ UsableRulesProof
QDP
                        ↳ QReductionProof

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

ADX(cons(X, L)) → ADX(L)

R is empty.
The set Q consists of the following terms:

adx(nil)
tail(cons(x0, x1))
zeros
adx(cons(x0, x1))
incr(nil)
head(cons(x0, x1))
nats
incr(cons(x0, x1))

We have to consider all minimal (P,Q,R)-chains.
We deleted the following terms from Q as each root-symbol of these terms does neither occur in P nor in R.

adx(nil)
tail(cons(x0, x1))
zeros
adx(cons(x0, x1))
incr(nil)
head(cons(x0, x1))
nats
incr(cons(x0, x1))



↳ QTRS
  ↳ RRRPoloQTRSProof
    ↳ QTRS
      ↳ RRRPoloQTRSProof
        ↳ QTRS
          ↳ DependencyPairsProof
            ↳ QDP
              ↳ DependencyGraphProof
                ↳ AND
                  ↳ QDP
                  ↳ QDP
                  ↳ QDP
                    ↳ UsableRulesProof
                      ↳ QDP
                        ↳ QReductionProof
QDP
                            ↳ QDPSizeChangeProof

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

ADX(cons(X, L)) → ADX(L)

R is empty.
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
By using the subterm criterion [20] together with the size-change analysis [32] we have proven that there are no infinite chains for this DP problem.

From the DPs we obtained the following set of size-change graphs: