Termination of the given ITRSProblem could successfully be proven:



ITRS
  ↳ ITRStoIDPProof

ITRS problem:
The following domains are used:

z

The TRS R consists of the following rules:

cond2(FALSE, x, y) → +@z(1@z, diff(+@z(x, 1@z), y))
cond1(TRUE, x, y) → 0@z
cond2(TRUE, x, y) → +@z(1@z, diff(x, +@z(y, 1@z)))
diff(x, y) → cond1(=@z(x, y), x, y)
cond1(FALSE, x, y) → cond2(>@z(x, y), x, y)

The set Q consists of the following terms:

cond2(FALSE, x0, x1)
cond1(TRUE, x0, x1)
cond2(TRUE, x0, x1)
diff(x0, x1)
cond1(FALSE, x0, x1)


Added dependency pairs

↳ ITRS
  ↳ ITRStoIDPProof
IDP
      ↳ UsableRulesProof

I DP problem:
The following domains are used:

z

The ITRS R consists of the following rules:

cond2(FALSE, x, y) → +@z(1@z, diff(+@z(x, 1@z), y))
cond1(TRUE, x, y) → 0@z
cond2(TRUE, x, y) → +@z(1@z, diff(x, +@z(y, 1@z)))
diff(x, y) → cond1(=@z(x, y), x, y)
cond1(FALSE, x, y) → cond2(>@z(x, y), x, y)

The integer pair graph contains the following rules and edges:

(0): COND2(FALSE, x[0], y[0]) → DIFF(+@z(x[0], 1@z), y[0])
(1): COND1(FALSE, x[1], y[1]) → COND2(>@z(x[1], y[1]), x[1], y[1])
(2): DIFF(x[2], y[2]) → COND1(=@z(x[2], y[2]), x[2], y[2])
(3): COND2(TRUE, x[3], y[3]) → DIFF(x[3], +@z(y[3], 1@z))

(0) -> (2), if ((y[0]* y[2])∧(+@z(x[0], 1@z) →* x[2]))


(1) -> (0), if ((x[1]* x[0])∧(y[1]* y[0])∧(>@z(x[1], y[1]) →* FALSE))


(1) -> (3), if ((x[1]* x[3])∧(y[1]* y[3])∧(>@z(x[1], y[1]) →* TRUE))


(2) -> (1), if ((x[2]* x[1])∧(y[2]* y[1])∧(=@z(x[2], y[2]) →* FALSE))


(3) -> (2), if ((+@z(y[3], 1@z) →* y[2])∧(x[3]* x[2]))



The set Q consists of the following terms:

cond2(FALSE, x0, x1)
cond1(TRUE, x0, x1)
cond2(TRUE, x0, x1)
diff(x0, x1)
cond1(FALSE, x0, x1)


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.

↳ ITRS
  ↳ ITRStoIDPProof
    ↳ IDP
      ↳ UsableRulesProof
IDP
          ↳ IDPNonInfProof

I DP problem:
The following domains are used:

z

R is empty.
The integer pair graph contains the following rules and edges:

(0): COND2(FALSE, x[0], y[0]) → DIFF(+@z(x[0], 1@z), y[0])
(1): COND1(FALSE, x[1], y[1]) → COND2(>@z(x[1], y[1]), x[1], y[1])
(2): DIFF(x[2], y[2]) → COND1(=@z(x[2], y[2]), x[2], y[2])
(3): COND2(TRUE, x[3], y[3]) → DIFF(x[3], +@z(y[3], 1@z))

(0) -> (2), if ((y[0]* y[2])∧(+@z(x[0], 1@z) →* x[2]))


(1) -> (0), if ((x[1]* x[0])∧(y[1]* y[0])∧(>@z(x[1], y[1]) →* FALSE))


(1) -> (3), if ((x[1]* x[3])∧(y[1]* y[3])∧(>@z(x[1], y[1]) →* TRUE))


(2) -> (1), if ((x[2]* x[1])∧(y[2]* y[1])∧(=@z(x[2], y[2]) →* FALSE))


(3) -> (2), if ((+@z(y[3], 1@z) →* y[2])∧(x[3]* x[2]))



The set Q consists of the following terms:

cond2(FALSE, x0, x1)
cond1(TRUE, x0, x1)
cond2(TRUE, x0, x1)
diff(x0, x1)
cond1(FALSE, x0, x1)


The constraints were generated the following way:
The DP Problem is simplified using the Induction Calculus [NONINF] with the following steps:
Note that final constraints are written in bold face.


For Pair COND2(FALSE, x, y) → DIFF(+@z(x, 1@z), y) the following chains were created:




For Pair COND1(FALSE, x, y) → COND2(>@z(x, y), x, y) the following chains were created:




For Pair DIFF(x, y) → COND1(=@z(x, y), x, y) the following chains were created:




For Pair COND2(TRUE, x, y) → DIFF(x, +@z(y, 1@z)) the following chains were created:




To summarize, we get the following constraints P for the following pairs.



The constraints for P> respective Pbound are constructed from P where we just replace every occurence of "t ≥ s" in P by "t > s" respective "t ≥ c". Here c stands for the fresh constant used for Pbound.
Using the following integer polynomial ordering the resulting constraints can be solved
Polynomial interpretation over integers[POLO]:

POL(DIFF(x1, x2)) = -1 + max{(-1)x1 + x2, x1 + (-1)x2}   
POL(=@z(x1, x2)) = -1   
POL(TRUE) = -1   
POL(COND2(x1, x2, x3)) = -1 + max{(-1)x2 + x3, x2 + (-1)x3}   
POL(+@z(x1, x2)) = x1 + x2   
POL(FALSE) = -1   
POL(COND1(x1, x2, x3)) = -1 + max{(-1)x2 + x3, x2 + (-1)x3}   
POL(1@z) = 1   
POL(undefined) = -1   
POL(>@z(x1, x2)) = -1   

The following pairs are in P>:

COND2(FALSE, x[0], y[0]) → DIFF(+@z(x[0], 1@z), y[0])

The following pairs are in Pbound:

COND2(FALSE, x[0], y[0]) → DIFF(+@z(x[0], 1@z), y[0])

The following pairs are in P:

COND1(FALSE, x[1], y[1]) → COND2(>@z(x[1], y[1]), x[1], y[1])
DIFF(x[2], y[2]) → COND1(=@z(x[2], y[2]), x[2], y[2])
COND2(TRUE, x[3], y[3]) → DIFF(x[3], +@z(y[3], 1@z))

At least the following rules have been oriented under context sensitive arithmetic replacement:

+@z1


↳ ITRS
  ↳ ITRStoIDPProof
    ↳ IDP
      ↳ UsableRulesProof
        ↳ IDP
          ↳ IDPNonInfProof
IDP
              ↳ IDPNonInfProof

I DP problem:
The following domains are used:

z

R is empty.
The integer pair graph contains the following rules and edges:

(1): COND1(FALSE, x[1], y[1]) → COND2(>@z(x[1], y[1]), x[1], y[1])
(2): DIFF(x[2], y[2]) → COND1(=@z(x[2], y[2]), x[2], y[2])
(3): COND2(TRUE, x[3], y[3]) → DIFF(x[3], +@z(y[3], 1@z))

(2) -> (1), if ((x[2]* x[1])∧(y[2]* y[1])∧(=@z(x[2], y[2]) →* FALSE))


(3) -> (2), if ((+@z(y[3], 1@z) →* y[2])∧(x[3]* x[2]))


(1) -> (3), if ((x[1]* x[3])∧(y[1]* y[3])∧(>@z(x[1], y[1]) →* TRUE))



The set Q consists of the following terms:

cond2(FALSE, x0, x1)
cond1(TRUE, x0, x1)
cond2(TRUE, x0, x1)
diff(x0, x1)
cond1(FALSE, x0, x1)


The constraints were generated the following way:
The DP Problem is simplified using the Induction Calculus [NONINF] with the following steps:
Note that final constraints are written in bold face.


For Pair COND1(FALSE, x[1], y[1]) → COND2(>@z(x[1], y[1]), x[1], y[1]) the following chains were created:




For Pair DIFF(x[2], y[2]) → COND1(=@z(x[2], y[2]), x[2], y[2]) the following chains were created:




For Pair COND2(TRUE, x[3], y[3]) → DIFF(x[3], +@z(y[3], 1@z)) the following chains were created:




To summarize, we get the following constraints P for the following pairs.



The constraints for P> respective Pbound are constructed from P where we just replace every occurence of "t ≥ s" in P by "t > s" respective "t ≥ c". Here c stands for the fresh constant used for Pbound.
Using the following integer polynomial ordering the resulting constraints can be solved
Polynomial interpretation over integers[POLO]:

POL(DIFF(x1, x2)) = (-1)x2 + x1   
POL(=@z(x1, x2)) = 1   
POL(TRUE) = -1   
POL(COND2(x1, x2, x3)) = -1 + (-1)x3 + x2   
POL(+@z(x1, x2)) = x1 + x2   
POL(FALSE) = 2   
POL(1@z) = 1   
POL(COND1(x1, x2, x3)) = (-1)x3 + x2   
POL(undefined) = -1   
POL(>@z(x1, x2)) = -1   

The following pairs are in P>:

COND1(FALSE, x[1], y[1]) → COND2(>@z(x[1], y[1]), x[1], y[1])

The following pairs are in Pbound:

COND2(TRUE, x[3], y[3]) → DIFF(x[3], +@z(y[3], 1@z))

The following pairs are in P:

DIFF(x[2], y[2]) → COND1(=@z(x[2], y[2]), x[2], y[2])
COND2(TRUE, x[3], y[3]) → DIFF(x[3], +@z(y[3], 1@z))

At least the following rules have been oriented under context sensitive arithmetic replacement:

+@z1


↳ ITRS
  ↳ ITRStoIDPProof
    ↳ IDP
      ↳ UsableRulesProof
        ↳ IDP
          ↳ IDPNonInfProof
            ↳ IDP
              ↳ IDPNonInfProof
                ↳ AND
IDP
                    ↳ IDependencyGraphProof
                  ↳ IDP

I DP problem:
The following domains are used:

z

R is empty.
The integer pair graph contains the following rules and edges:

(1): COND1(FALSE, x[1], y[1]) → COND2(>@z(x[1], y[1]), x[1], y[1])
(2): DIFF(x[2], y[2]) → COND1(=@z(x[2], y[2]), x[2], y[2])

(2) -> (1), if ((x[2]* x[1])∧(y[2]* y[1])∧(=@z(x[2], y[2]) →* FALSE))



The set Q consists of the following terms:

cond2(FALSE, x0, x1)
cond1(TRUE, x0, x1)
cond2(TRUE, x0, x1)
diff(x0, x1)
cond1(FALSE, x0, x1)


The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 0 SCCs with 2 less nodes.

↳ ITRS
  ↳ ITRStoIDPProof
    ↳ IDP
      ↳ UsableRulesProof
        ↳ IDP
          ↳ IDPNonInfProof
            ↳ IDP
              ↳ IDPNonInfProof
                ↳ AND
                  ↳ IDP
IDP
                    ↳ IDependencyGraphProof

I DP problem:
The following domains are used:

z

R is empty.
The integer pair graph contains the following rules and edges:

(2): DIFF(x[2], y[2]) → COND1(=@z(x[2], y[2]), x[2], y[2])
(3): COND2(TRUE, x[3], y[3]) → DIFF(x[3], +@z(y[3], 1@z))

(3) -> (2), if ((+@z(y[3], 1@z) →* y[2])∧(x[3]* x[2]))



The set Q consists of the following terms:

cond2(FALSE, x0, x1)
cond1(TRUE, x0, x1)
cond2(TRUE, x0, x1)
diff(x0, x1)
cond1(FALSE, x0, x1)


The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 0 SCCs with 2 less nodes.