Termination w.r.t. Q of the following Term Rewriting System could not be shown:

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

minus2(x, 0) -> x
minus2(s1(x), s1(y)) -> minus2(x, y)
double1(0) -> 0
double1(s1(x)) -> s1(s1(double1(x)))
plus2(0, y) -> y
plus2(s1(x), y) -> s1(plus2(x, y))
plus2(s1(x), y) -> plus2(x, s1(y))
plus2(s1(x), y) -> s1(plus2(minus2(x, y), double1(y)))
plus2(s1(plus2(x, y)), z) -> s1(plus2(plus2(x, y), z))

Q is empty.


↳ QTRS
  ↳ DependencyPairsProof

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

minus2(x, 0) -> x
minus2(s1(x), s1(y)) -> minus2(x, y)
double1(0) -> 0
double1(s1(x)) -> s1(s1(double1(x)))
plus2(0, y) -> y
plus2(s1(x), y) -> s1(plus2(x, y))
plus2(s1(x), y) -> plus2(x, s1(y))
plus2(s1(x), y) -> s1(plus2(minus2(x, y), double1(y)))
plus2(s1(plus2(x, y)), z) -> s1(plus2(plus2(x, y), z))

Q is empty.

Using Dependency Pairs [1,13] we result in the following initial DP problem:
Q DP problem:
The TRS P consists of the following rules:

DOUBLE1(s1(x)) -> DOUBLE1(x)
PLUS2(s1(x), y) -> PLUS2(x, y)
PLUS2(s1(x), y) -> MINUS2(x, y)
PLUS2(s1(x), y) -> DOUBLE1(y)
PLUS2(s1(x), y) -> PLUS2(x, s1(y))
PLUS2(s1(plus2(x, y)), z) -> PLUS2(plus2(x, y), z)
MINUS2(s1(x), s1(y)) -> MINUS2(x, y)
PLUS2(s1(x), y) -> PLUS2(minus2(x, y), double1(y))

The TRS R consists of the following rules:

minus2(x, 0) -> x
minus2(s1(x), s1(y)) -> minus2(x, y)
double1(0) -> 0
double1(s1(x)) -> s1(s1(double1(x)))
plus2(0, y) -> y
plus2(s1(x), y) -> s1(plus2(x, y))
plus2(s1(x), y) -> plus2(x, s1(y))
plus2(s1(x), y) -> s1(plus2(minus2(x, y), double1(y)))
plus2(s1(plus2(x, y)), z) -> s1(plus2(plus2(x, y), z))

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

↳ QTRS
  ↳ DependencyPairsProof
    ↳ QDP
      ↳ DependencyGraphProof

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

DOUBLE1(s1(x)) -> DOUBLE1(x)
PLUS2(s1(x), y) -> PLUS2(x, y)
PLUS2(s1(x), y) -> MINUS2(x, y)
PLUS2(s1(x), y) -> DOUBLE1(y)
PLUS2(s1(x), y) -> PLUS2(x, s1(y))
PLUS2(s1(plus2(x, y)), z) -> PLUS2(plus2(x, y), z)
MINUS2(s1(x), s1(y)) -> MINUS2(x, y)
PLUS2(s1(x), y) -> PLUS2(minus2(x, y), double1(y))

The TRS R consists of the following rules:

minus2(x, 0) -> x
minus2(s1(x), s1(y)) -> minus2(x, y)
double1(0) -> 0
double1(s1(x)) -> s1(s1(double1(x)))
plus2(0, y) -> y
plus2(s1(x), y) -> s1(plus2(x, y))
plus2(s1(x), y) -> plus2(x, s1(y))
plus2(s1(x), y) -> s1(plus2(minus2(x, y), double1(y)))
plus2(s1(plus2(x, y)), z) -> s1(plus2(plus2(x, y), z))

Q is empty.
We have to consider all minimal (P,Q,R)-chains.
The approximation of the Dependency Graph [13,14,18] contains 3 SCCs with 2 less nodes.

↳ QTRS
  ↳ DependencyPairsProof
    ↳ QDP
      ↳ DependencyGraphProof
        ↳ AND
          ↳ QDP
            ↳ QDPOrderProof
          ↳ QDP
          ↳ QDP

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

DOUBLE1(s1(x)) -> DOUBLE1(x)

The TRS R consists of the following rules:

minus2(x, 0) -> x
minus2(s1(x), s1(y)) -> minus2(x, y)
double1(0) -> 0
double1(s1(x)) -> s1(s1(double1(x)))
plus2(0, y) -> y
plus2(s1(x), y) -> s1(plus2(x, y))
plus2(s1(x), y) -> plus2(x, s1(y))
plus2(s1(x), y) -> s1(plus2(minus2(x, y), double1(y)))
plus2(s1(plus2(x, y)), z) -> s1(plus2(plus2(x, y), z))

Q is empty.
We have to consider all minimal (P,Q,R)-chains.
We use the reduction pair processor [13].


The following pairs can be oriented strictly and are deleted.


DOUBLE1(s1(x)) -> DOUBLE1(x)
The remaining pairs can at least be oriented weakly.
none
Used ordering: Polynomial Order [17,21] with Interpretation:

POL( DOUBLE1(x1) ) = max{0, x1 - 2}


POL( s1(x1) ) = x1 + 3



The following usable rules [14] were oriented: none



↳ QTRS
  ↳ DependencyPairsProof
    ↳ QDP
      ↳ DependencyGraphProof
        ↳ AND
          ↳ QDP
            ↳ QDPOrderProof
              ↳ QDP
                ↳ PisEmptyProof
          ↳ QDP
          ↳ QDP

Q DP problem:
P is empty.
The TRS R consists of the following rules:

minus2(x, 0) -> x
minus2(s1(x), s1(y)) -> minus2(x, y)
double1(0) -> 0
double1(s1(x)) -> s1(s1(double1(x)))
plus2(0, y) -> y
plus2(s1(x), y) -> s1(plus2(x, y))
plus2(s1(x), y) -> plus2(x, s1(y))
plus2(s1(x), y) -> s1(plus2(minus2(x, y), double1(y)))
plus2(s1(plus2(x, y)), z) -> s1(plus2(plus2(x, y), z))

Q is empty.
We have to consider all minimal (P,Q,R)-chains.
The TRS P is empty. Hence, there is no (P,Q,R) chain.

↳ QTRS
  ↳ DependencyPairsProof
    ↳ QDP
      ↳ DependencyGraphProof
        ↳ AND
          ↳ QDP
          ↳ QDP
            ↳ QDPOrderProof
          ↳ QDP

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

MINUS2(s1(x), s1(y)) -> MINUS2(x, y)

The TRS R consists of the following rules:

minus2(x, 0) -> x
minus2(s1(x), s1(y)) -> minus2(x, y)
double1(0) -> 0
double1(s1(x)) -> s1(s1(double1(x)))
plus2(0, y) -> y
plus2(s1(x), y) -> s1(plus2(x, y))
plus2(s1(x), y) -> plus2(x, s1(y))
plus2(s1(x), y) -> s1(plus2(minus2(x, y), double1(y)))
plus2(s1(plus2(x, y)), z) -> s1(plus2(plus2(x, y), z))

Q is empty.
We have to consider all minimal (P,Q,R)-chains.
We use the reduction pair processor [13].


The following pairs can be oriented strictly and are deleted.


MINUS2(s1(x), s1(y)) -> MINUS2(x, y)
The remaining pairs can at least be oriented weakly.
none
Used ordering: Polynomial Order [17,21] with Interpretation:

POL( MINUS2(x1, x2) ) = max{0, x2 - 2}


POL( s1(x1) ) = x1 + 3



The following usable rules [14] were oriented: none



↳ QTRS
  ↳ DependencyPairsProof
    ↳ QDP
      ↳ DependencyGraphProof
        ↳ AND
          ↳ QDP
          ↳ QDP
            ↳ QDPOrderProof
              ↳ QDP
                ↳ PisEmptyProof
          ↳ QDP

Q DP problem:
P is empty.
The TRS R consists of the following rules:

minus2(x, 0) -> x
minus2(s1(x), s1(y)) -> minus2(x, y)
double1(0) -> 0
double1(s1(x)) -> s1(s1(double1(x)))
plus2(0, y) -> y
plus2(s1(x), y) -> s1(plus2(x, y))
plus2(s1(x), y) -> plus2(x, s1(y))
plus2(s1(x), y) -> s1(plus2(minus2(x, y), double1(y)))
plus2(s1(plus2(x, y)), z) -> s1(plus2(plus2(x, y), z))

Q is empty.
We have to consider all minimal (P,Q,R)-chains.
The TRS P is empty. Hence, there is no (P,Q,R) chain.

↳ QTRS
  ↳ DependencyPairsProof
    ↳ QDP
      ↳ DependencyGraphProof
        ↳ AND
          ↳ QDP
          ↳ QDP
          ↳ QDP

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

PLUS2(s1(x), y) -> PLUS2(x, y)
PLUS2(s1(x), y) -> PLUS2(x, s1(y))
PLUS2(s1(plus2(x, y)), z) -> PLUS2(plus2(x, y), z)
PLUS2(s1(x), y) -> PLUS2(minus2(x, y), double1(y))

The TRS R consists of the following rules:

minus2(x, 0) -> x
minus2(s1(x), s1(y)) -> minus2(x, y)
double1(0) -> 0
double1(s1(x)) -> s1(s1(double1(x)))
plus2(0, y) -> y
plus2(s1(x), y) -> s1(plus2(x, y))
plus2(s1(x), y) -> plus2(x, s1(y))
plus2(s1(x), y) -> s1(plus2(minus2(x, y), double1(y)))
plus2(s1(plus2(x, y)), z) -> s1(plus2(plus2(x, y), z))

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