Termination of the following Term Rewriting System could be proven:

Context-sensitive rewrite system:
The TRS R consists of the following rules:

U11(tt, V2) → U12(isNat(V2))
U12(tt) → tt
U21(tt) → tt
U31(tt, V2) → U32(isNat(V2))
U32(tt) → tt
U41(tt, N) → N
U51(tt, M, N) → U52(isNat(N), M, N)
U52(tt, M, N) → s(plus(N, M))
U61(tt) → 0
U71(tt, M, N) → U72(isNat(N), M, N)
U72(tt, M, N) → plus(x(N, M), N)
isNat(0) → tt
isNat(plus(V1, V2)) → U11(isNat(V1), V2)
isNat(s(V1)) → U21(isNat(V1))
isNat(x(V1, V2)) → U31(isNat(V1), V2)
plus(N, 0) → U41(isNat(N), N)
plus(N, s(M)) → U51(isNat(M), M, N)
x(N, 0) → U61(isNat(N))
x(N, s(M)) → U71(isNat(M), M, N)

The replacement map contains the following entries:

U11: {1}
tt: empty set
U12: {1}
isNat: empty set
U21: {1}
U31: {1}
U32: {1}
U41: {1}
U51: {1}
U52: {1}
s: {1}
plus: {1, 2}
U61: {1}
0: empty set
U71: {1}
U72: {1}
x: {1, 2}


CSR
  ↳ CSDependencyPairsProof

Context-sensitive rewrite system:
The TRS R consists of the following rules:

U11(tt, V2) → U12(isNat(V2))
U12(tt) → tt
U21(tt) → tt
U31(tt, V2) → U32(isNat(V2))
U32(tt) → tt
U41(tt, N) → N
U51(tt, M, N) → U52(isNat(N), M, N)
U52(tt, M, N) → s(plus(N, M))
U61(tt) → 0
U71(tt, M, N) → U72(isNat(N), M, N)
U72(tt, M, N) → plus(x(N, M), N)
isNat(0) → tt
isNat(plus(V1, V2)) → U11(isNat(V1), V2)
isNat(s(V1)) → U21(isNat(V1))
isNat(x(V1, V2)) → U31(isNat(V1), V2)
plus(N, 0) → U41(isNat(N), N)
plus(N, s(M)) → U51(isNat(M), M, N)
x(N, 0) → U61(isNat(N))
x(N, s(M)) → U71(isNat(M), M, N)

The replacement map contains the following entries:

U11: {1}
tt: empty set
U12: {1}
isNat: empty set
U21: {1}
U31: {1}
U32: {1}
U41: {1}
U51: {1}
U52: {1}
s: {1}
plus: {1, 2}
U61: {1}
0: empty set
U71: {1}
U72: {1}
x: {1, 2}

Using Improved CS-DPs we result in the following initial Q-CSDP problem.

↳ CSR
  ↳ CSDependencyPairsProof
QCSDP
      ↳ QCSDependencyGraphProof

Q-restricted context-sensitive dependency pair problem:
The symbols in {U12, U21, U32, s, plus, U61, x, U121, U321, PLUS, X, U211, U611} are replacing on all positions.
For all symbols f in {U11, U31, U41, U51, U52, U71, U72, U111, U311, U521, U511, U721, U711, U411} we have µ(f) = {1}.
The symbols in {isNat, ISNAT, U} are not replacing on any position.

The ordinary context-sensitive dependency pairs DPo are:

U111(tt, V2) → U121(isNat(V2))
U111(tt, V2) → ISNAT(V2)
U311(tt, V2) → U321(isNat(V2))
U311(tt, V2) → ISNAT(V2)
U511(tt, M, N) → U521(isNat(N), M, N)
U511(tt, M, N) → ISNAT(N)
U521(tt, M, N) → PLUS(N, M)
U711(tt, M, N) → U721(isNat(N), M, N)
U711(tt, M, N) → ISNAT(N)
U721(tt, M, N) → PLUS(x(N, M), N)
U721(tt, M, N) → X(N, M)
ISNAT(plus(V1, V2)) → U111(isNat(V1), V2)
ISNAT(plus(V1, V2)) → ISNAT(V1)
ISNAT(s(V1)) → U211(isNat(V1))
ISNAT(s(V1)) → ISNAT(V1)
ISNAT(x(V1, V2)) → U311(isNat(V1), V2)
ISNAT(x(V1, V2)) → ISNAT(V1)
PLUS(N, 0) → U411(isNat(N), N)
PLUS(N, 0) → ISNAT(N)
PLUS(N, s(M)) → U511(isNat(M), M, N)
PLUS(N, s(M)) → ISNAT(M)
X(N, 0) → U611(isNat(N))
X(N, 0) → ISNAT(N)
X(N, s(M)) → U711(isNat(M), M, N)
X(N, s(M)) → ISNAT(M)

The collapsing dependency pairs are DPc:

U411(tt, N) → N
U521(tt, M, N) → N
U521(tt, M, N) → M
U721(tt, M, N) → N
U721(tt, M, N) → M


The hidden terms of R are:
none

Every hiding context is built from:none

Hence, the new unhiding pairs DPu are :

U411(tt, N) → U(N)
U521(tt, M, N) → U(N)
U521(tt, M, N) → U(M)
U721(tt, M, N) → U(N)
U721(tt, M, N) → U(M)

The TRS R consists of the following rules:

U11(tt, V2) → U12(isNat(V2))
U12(tt) → tt
U21(tt) → tt
U31(tt, V2) → U32(isNat(V2))
U32(tt) → tt
U41(tt, N) → N
U51(tt, M, N) → U52(isNat(N), M, N)
U52(tt, M, N) → s(plus(N, M))
U61(tt) → 0
U71(tt, M, N) → U72(isNat(N), M, N)
U72(tt, M, N) → plus(x(N, M), N)
isNat(0) → tt
isNat(plus(V1, V2)) → U11(isNat(V1), V2)
isNat(s(V1)) → U21(isNat(V1))
isNat(x(V1, V2)) → U31(isNat(V1), V2)
plus(N, 0) → U41(isNat(N), N)
plus(N, s(M)) → U51(isNat(M), M, N)
x(N, 0) → U61(isNat(N))
x(N, s(M)) → U71(isNat(M), M, N)

Q is empty.

The approximation of the Context-Sensitive Dependency Graph contains 3 SCCs with 17 less nodes.


↳ CSR
  ↳ CSDependencyPairsProof
    ↳ QCSDP
      ↳ QCSDependencyGraphProof
        ↳ AND
QCSDP
            ↳ QCSDPSubtermProof
          ↳ QCSDP
          ↳ QCSDP

Q-restricted context-sensitive dependency pair problem:
The symbols in {U12, U21, U32, s, plus, U61, x} are replacing on all positions.
For all symbols f in {U11, U31, U41, U51, U52, U71, U72, U111, U311} we have µ(f) = {1}.
The symbols in {isNat, ISNAT} are not replacing on any position.

The TRS P consists of the following rules:

ISNAT(plus(V1, V2)) → U111(isNat(V1), V2)
U111(tt, V2) → ISNAT(V2)
ISNAT(plus(V1, V2)) → ISNAT(V1)
ISNAT(s(V1)) → ISNAT(V1)
ISNAT(x(V1, V2)) → U311(isNat(V1), V2)
U311(tt, V2) → ISNAT(V2)
ISNAT(x(V1, V2)) → ISNAT(V1)

The TRS R consists of the following rules:

U11(tt, V2) → U12(isNat(V2))
U12(tt) → tt
U21(tt) → tt
U31(tt, V2) → U32(isNat(V2))
U32(tt) → tt
U41(tt, N) → N
U51(tt, M, N) → U52(isNat(N), M, N)
U52(tt, M, N) → s(plus(N, M))
U61(tt) → 0
U71(tt, M, N) → U72(isNat(N), M, N)
U72(tt, M, N) → plus(x(N, M), N)
isNat(0) → tt
isNat(plus(V1, V2)) → U11(isNat(V1), V2)
isNat(s(V1)) → U21(isNat(V1))
isNat(x(V1, V2)) → U31(isNat(V1), V2)
plus(N, 0) → U41(isNat(N), N)
plus(N, s(M)) → U51(isNat(M), M, N)
x(N, 0) → U61(isNat(N))
x(N, s(M)) → U71(isNat(M), M, N)

Q is empty.

We use the subterm processor [20].


The following pairs can be oriented strictly and are deleted.


ISNAT(plus(V1, V2)) → U111(isNat(V1), V2)
ISNAT(plus(V1, V2)) → ISNAT(V1)
ISNAT(s(V1)) → ISNAT(V1)
ISNAT(x(V1, V2)) → U311(isNat(V1), V2)
ISNAT(x(V1, V2)) → ISNAT(V1)
The remaining pairs can at least be oriented weakly.

U111(tt, V2) → ISNAT(V2)
U311(tt, V2) → ISNAT(V2)
Used ordering: Combined order from the following AFS and order.
U111(x1, x2)  =  x2
ISNAT(x1)  =  x1
U311(x1, x2)  =  x2

Subterm Order


↳ CSR
  ↳ CSDependencyPairsProof
    ↳ QCSDP
      ↳ QCSDependencyGraphProof
        ↳ AND
          ↳ QCSDP
            ↳ QCSDPSubtermProof
QCSDP
                ↳ QCSDependencyGraphProof
          ↳ QCSDP
          ↳ QCSDP

Q-restricted context-sensitive dependency pair problem:
The symbols in {U12, U21, U32, s, plus, U61, x} are replacing on all positions.
For all symbols f in {U11, U31, U41, U51, U52, U71, U72, U111, U311} we have µ(f) = {1}.
The symbols in {isNat, ISNAT} are not replacing on any position.

The TRS P consists of the following rules:

U111(tt, V2) → ISNAT(V2)
U311(tt, V2) → ISNAT(V2)

The TRS R consists of the following rules:

U11(tt, V2) → U12(isNat(V2))
U12(tt) → tt
U21(tt) → tt
U31(tt, V2) → U32(isNat(V2))
U32(tt) → tt
U41(tt, N) → N
U51(tt, M, N) → U52(isNat(N), M, N)
U52(tt, M, N) → s(plus(N, M))
U61(tt) → 0
U71(tt, M, N) → U72(isNat(N), M, N)
U72(tt, M, N) → plus(x(N, M), N)
isNat(0) → tt
isNat(plus(V1, V2)) → U11(isNat(V1), V2)
isNat(s(V1)) → U21(isNat(V1))
isNat(x(V1, V2)) → U31(isNat(V1), V2)
plus(N, 0) → U41(isNat(N), N)
plus(N, s(M)) → U51(isNat(M), M, N)
x(N, 0) → U61(isNat(N))
x(N, s(M)) → U71(isNat(M), M, N)

Q is empty.

The approximation of the Context-Sensitive Dependency Graph contains 0 SCCs.


↳ CSR
  ↳ CSDependencyPairsProof
    ↳ QCSDP
      ↳ QCSDependencyGraphProof
        ↳ AND
          ↳ QCSDP
QCSDP
            ↳ QCSDPSubtermProof
          ↳ QCSDP

Q-restricted context-sensitive dependency pair problem:
The symbols in {U12, U21, U32, s, plus, U61, x, PLUS} are replacing on all positions.
For all symbols f in {U11, U31, U41, U51, U52, U71, U72, U521, U511} we have µ(f) = {1}.
The symbols in {isNat} are not replacing on any position.

The TRS P consists of the following rules:

U511(tt, M, N) → U521(isNat(N), M, N)
U521(tt, M, N) → PLUS(N, M)
PLUS(N, s(M)) → U511(isNat(M), M, N)

The TRS R consists of the following rules:

U11(tt, V2) → U12(isNat(V2))
U12(tt) → tt
U21(tt) → tt
U31(tt, V2) → U32(isNat(V2))
U32(tt) → tt
U41(tt, N) → N
U51(tt, M, N) → U52(isNat(N), M, N)
U52(tt, M, N) → s(plus(N, M))
U61(tt) → 0
U71(tt, M, N) → U72(isNat(N), M, N)
U72(tt, M, N) → plus(x(N, M), N)
isNat(0) → tt
isNat(plus(V1, V2)) → U11(isNat(V1), V2)
isNat(s(V1)) → U21(isNat(V1))
isNat(x(V1, V2)) → U31(isNat(V1), V2)
plus(N, 0) → U41(isNat(N), N)
plus(N, s(M)) → U51(isNat(M), M, N)
x(N, 0) → U61(isNat(N))
x(N, s(M)) → U71(isNat(M), M, N)

Q is empty.

We use the subterm processor [20].


The following pairs can be oriented strictly and are deleted.


PLUS(N, s(M)) → U511(isNat(M), M, N)
The remaining pairs can at least be oriented weakly.

U511(tt, M, N) → U521(isNat(N), M, N)
U521(tt, M, N) → PLUS(N, M)
Used ordering: Combined order from the following AFS and order.
U521(x1, x2, x3)  =  x2
U511(x1, x2, x3)  =  x2
PLUS(x1, x2)  =  x2

Subterm Order


↳ CSR
  ↳ CSDependencyPairsProof
    ↳ QCSDP
      ↳ QCSDependencyGraphProof
        ↳ AND
          ↳ QCSDP
          ↳ QCSDP
            ↳ QCSDPSubtermProof
QCSDP
                ↳ QCSDependencyGraphProof
          ↳ QCSDP

Q-restricted context-sensitive dependency pair problem:
The symbols in {U12, U21, U32, s, plus, U61, x, PLUS} are replacing on all positions.
For all symbols f in {U11, U31, U41, U51, U52, U71, U72, U521, U511} we have µ(f) = {1}.
The symbols in {isNat} are not replacing on any position.

The TRS P consists of the following rules:

U511(tt, M, N) → U521(isNat(N), M, N)
U521(tt, M, N) → PLUS(N, M)

The TRS R consists of the following rules:

U11(tt, V2) → U12(isNat(V2))
U12(tt) → tt
U21(tt) → tt
U31(tt, V2) → U32(isNat(V2))
U32(tt) → tt
U41(tt, N) → N
U51(tt, M, N) → U52(isNat(N), M, N)
U52(tt, M, N) → s(plus(N, M))
U61(tt) → 0
U71(tt, M, N) → U72(isNat(N), M, N)
U72(tt, M, N) → plus(x(N, M), N)
isNat(0) → tt
isNat(plus(V1, V2)) → U11(isNat(V1), V2)
isNat(s(V1)) → U21(isNat(V1))
isNat(x(V1, V2)) → U31(isNat(V1), V2)
plus(N, 0) → U41(isNat(N), N)
plus(N, s(M)) → U51(isNat(M), M, N)
x(N, 0) → U61(isNat(N))
x(N, s(M)) → U71(isNat(M), M, N)

Q is empty.

The approximation of the Context-Sensitive Dependency Graph contains 0 SCCs with 2 less nodes.


↳ CSR
  ↳ CSDependencyPairsProof
    ↳ QCSDP
      ↳ QCSDependencyGraphProof
        ↳ AND
          ↳ QCSDP
          ↳ QCSDP
QCSDP
            ↳ QCSDPSubtermProof

Q-restricted context-sensitive dependency pair problem:
The symbols in {U12, U21, U32, s, plus, U61, x, X} are replacing on all positions.
For all symbols f in {U11, U31, U41, U51, U52, U71, U72, U721, U711} we have µ(f) = {1}.
The symbols in {isNat} are not replacing on any position.

The TRS P consists of the following rules:

U721(tt, M, N) → X(N, M)
X(N, s(M)) → U711(isNat(M), M, N)
U711(tt, M, N) → U721(isNat(N), M, N)

The TRS R consists of the following rules:

U11(tt, V2) → U12(isNat(V2))
U12(tt) → tt
U21(tt) → tt
U31(tt, V2) → U32(isNat(V2))
U32(tt) → tt
U41(tt, N) → N
U51(tt, M, N) → U52(isNat(N), M, N)
U52(tt, M, N) → s(plus(N, M))
U61(tt) → 0
U71(tt, M, N) → U72(isNat(N), M, N)
U72(tt, M, N) → plus(x(N, M), N)
isNat(0) → tt
isNat(plus(V1, V2)) → U11(isNat(V1), V2)
isNat(s(V1)) → U21(isNat(V1))
isNat(x(V1, V2)) → U31(isNat(V1), V2)
plus(N, 0) → U41(isNat(N), N)
plus(N, s(M)) → U51(isNat(M), M, N)
x(N, 0) → U61(isNat(N))
x(N, s(M)) → U71(isNat(M), M, N)

Q is empty.

We use the subterm processor [20].


The following pairs can be oriented strictly and are deleted.


X(N, s(M)) → U711(isNat(M), M, N)
The remaining pairs can at least be oriented weakly.

U721(tt, M, N) → X(N, M)
U711(tt, M, N) → U721(isNat(N), M, N)
Used ordering: Combined order from the following AFS and order.
X(x1, x2)  =  x2
U721(x1, x2, x3)  =  x2
U711(x1, x2, x3)  =  x2

Subterm Order


↳ CSR
  ↳ CSDependencyPairsProof
    ↳ QCSDP
      ↳ QCSDependencyGraphProof
        ↳ AND
          ↳ QCSDP
          ↳ QCSDP
          ↳ QCSDP
            ↳ QCSDPSubtermProof
QCSDP
                ↳ QCSDependencyGraphProof

Q-restricted context-sensitive dependency pair problem:
The symbols in {U12, U21, U32, s, plus, U61, x, X} are replacing on all positions.
For all symbols f in {U11, U31, U41, U51, U52, U71, U72, U721, U711} we have µ(f) = {1}.
The symbols in {isNat} are not replacing on any position.

The TRS P consists of the following rules:

U721(tt, M, N) → X(N, M)
U711(tt, M, N) → U721(isNat(N), M, N)

The TRS R consists of the following rules:

U11(tt, V2) → U12(isNat(V2))
U12(tt) → tt
U21(tt) → tt
U31(tt, V2) → U32(isNat(V2))
U32(tt) → tt
U41(tt, N) → N
U51(tt, M, N) → U52(isNat(N), M, N)
U52(tt, M, N) → s(plus(N, M))
U61(tt) → 0
U71(tt, M, N) → U72(isNat(N), M, N)
U72(tt, M, N) → plus(x(N, M), N)
isNat(0) → tt
isNat(plus(V1, V2)) → U11(isNat(V1), V2)
isNat(s(V1)) → U21(isNat(V1))
isNat(x(V1, V2)) → U31(isNat(V1), V2)
plus(N, 0) → U41(isNat(N), N)
plus(N, s(M)) → U51(isNat(M), M, N)
x(N, 0) → U61(isNat(N))
x(N, s(M)) → U71(isNat(M), M, N)

Q is empty.

The approximation of the Context-Sensitive Dependency Graph contains 0 SCCs with 2 less nodes.