Term Rewriting System R:
[X, Y, Z, X1, X2]
asel(0, cons(X, Y)) -> mark(X)
asel(s(X), cons(Y, Z)) -> asel(mark(X), mark(Z))
asel(X1, X2) -> sel(X1, X2)
aindx(nil, X) -> nil
aindx(cons(X, Y), Z) -> cons(sel(X, Z), indx(Y, Z))
aindx(X1, X2) -> indx(X1, X2)
afrom(X) -> cons(X, from(s(X)))
afrom(X) -> from(X)
mark(sel(X1, X2)) -> asel(mark(X1), mark(X2))
mark(indx(X1, X2)) -> aindx(mark(X1), X2)
mark(from(X)) -> afrom(X)
mark(0) -> 0
mark(s(X)) -> s(X)
mark(nil) -> nil
mark(cons(X1, X2)) -> cons(X1, X2)

Termination of R to be shown.

`   R`
`     ↳Dependency Pair Analysis`

R contains the following Dependency Pairs:

ASEL(0, cons(X, Y)) -> MARK(X)
ASEL(s(X), cons(Y, Z)) -> ASEL(mark(X), mark(Z))
ASEL(s(X), cons(Y, Z)) -> MARK(X)
ASEL(s(X), cons(Y, Z)) -> MARK(Z)
MARK(dbl(X)) -> MARK(X)
MARK(dbls(X)) -> MARK(X)
MARK(sel(X1, X2)) -> ASEL(mark(X1), mark(X2))
MARK(sel(X1, X2)) -> MARK(X1)
MARK(sel(X1, X2)) -> MARK(X2)
MARK(indx(X1, X2)) -> AINDX(mark(X1), X2)
MARK(indx(X1, X2)) -> MARK(X1)
MARK(from(X)) -> AFROM(X)

Furthermore, R contains one SCC.

`   R`
`     ↳DPs`
`       →DP Problem 1`
`         ↳Narrowing Transformation`

Dependency Pairs:

ASEL(s(X), cons(Y, Z)) -> MARK(Z)
MARK(indx(X1, X2)) -> MARK(X1)
MARK(sel(X1, X2)) -> MARK(X2)
MARK(sel(X1, X2)) -> MARK(X1)
ASEL(s(X), cons(Y, Z)) -> MARK(X)
ASEL(s(X), cons(Y, Z)) -> ASEL(mark(X), mark(Z))
MARK(sel(X1, X2)) -> ASEL(mark(X1), mark(X2))
MARK(dbls(X)) -> MARK(X)
MARK(dbl(X)) -> MARK(X)
ASEL(0, cons(X, Y)) -> MARK(X)

Rules:

asel(0, cons(X, Y)) -> mark(X)
asel(s(X), cons(Y, Z)) -> asel(mark(X), mark(Z))
asel(X1, X2) -> sel(X1, X2)
aindx(nil, X) -> nil
aindx(cons(X, Y), Z) -> cons(sel(X, Z), indx(Y, Z))
aindx(X1, X2) -> indx(X1, X2)
afrom(X) -> cons(X, from(s(X)))
afrom(X) -> from(X)
mark(sel(X1, X2)) -> asel(mark(X1), mark(X2))
mark(indx(X1, X2)) -> aindx(mark(X1), X2)
mark(from(X)) -> afrom(X)
mark(0) -> 0
mark(s(X)) -> s(X)
mark(nil) -> nil
mark(cons(X1, X2)) -> cons(X1, X2)

On this DP problem, a Narrowing SCC transformation can be performed.
As a result of transforming the rule

ASEL(s(X), cons(Y, Z)) -> ASEL(mark(X), mark(Z))
18 new Dependency Pairs are created:

ASEL(s(dbl(X'')), cons(Y, Z)) -> ASEL(adbl(mark(X'')), mark(Z))
ASEL(s(dbls(X'')), cons(Y, Z)) -> ASEL(adbls(mark(X'')), mark(Z))
ASEL(s(sel(X1', X2')), cons(Y, Z)) -> ASEL(asel(mark(X1'), mark(X2')), mark(Z))
ASEL(s(indx(X1', X2')), cons(Y, Z)) -> ASEL(aindx(mark(X1'), X2'), mark(Z))
ASEL(s(from(X'')), cons(Y, Z)) -> ASEL(afrom(X''), mark(Z))
ASEL(s(0), cons(Y, Z)) -> ASEL(0, mark(Z))
ASEL(s(s(X'')), cons(Y, Z)) -> ASEL(s(X''), mark(Z))
ASEL(s(nil), cons(Y, Z)) -> ASEL(nil, mark(Z))
ASEL(s(cons(X1', X2')), cons(Y, Z)) -> ASEL(cons(X1', X2'), mark(Z))
ASEL(s(X), cons(Y, dbl(X''))) -> ASEL(mark(X), adbl(mark(X'')))
ASEL(s(X), cons(Y, dbls(X''))) -> ASEL(mark(X), adbls(mark(X'')))
ASEL(s(X), cons(Y, sel(X1', X2'))) -> ASEL(mark(X), asel(mark(X1'), mark(X2')))
ASEL(s(X), cons(Y, indx(X1', X2'))) -> ASEL(mark(X), aindx(mark(X1'), X2'))
ASEL(s(X), cons(Y, from(X''))) -> ASEL(mark(X), afrom(X''))
ASEL(s(X), cons(Y, 0)) -> ASEL(mark(X), 0)
ASEL(s(X), cons(Y, s(X''))) -> ASEL(mark(X), s(X''))
ASEL(s(X), cons(Y, nil)) -> ASEL(mark(X), nil)
ASEL(s(X), cons(Y, cons(X1', X2'))) -> ASEL(mark(X), cons(X1', X2'))

The transformation is resulting in one new DP problem:

`   R`
`     ↳DPs`
`       →DP Problem 1`
`         ↳Nar`
`           →DP Problem 2`
`             ↳Narrowing Transformation`

Dependency Pairs:

ASEL(s(X), cons(Y, cons(X1', X2'))) -> ASEL(mark(X), cons(X1', X2'))
ASEL(s(X), cons(Y, from(X''))) -> ASEL(mark(X), afrom(X''))
ASEL(s(X), cons(Y, indx(X1', X2'))) -> ASEL(mark(X), aindx(mark(X1'), X2'))
ASEL(s(X), cons(Y, sel(X1', X2'))) -> ASEL(mark(X), asel(mark(X1'), mark(X2')))
ASEL(s(X), cons(Y, dbls(X''))) -> ASEL(mark(X), adbls(mark(X'')))
ASEL(s(X), cons(Y, dbl(X''))) -> ASEL(mark(X), adbl(mark(X'')))
ASEL(s(s(X'')), cons(Y, Z)) -> ASEL(s(X''), mark(Z))
ASEL(s(0), cons(Y, Z)) -> ASEL(0, mark(Z))
ASEL(s(from(X'')), cons(Y, Z)) -> ASEL(afrom(X''), mark(Z))
ASEL(s(indx(X1', X2')), cons(Y, Z)) -> ASEL(aindx(mark(X1'), X2'), mark(Z))
ASEL(s(sel(X1', X2')), cons(Y, Z)) -> ASEL(asel(mark(X1'), mark(X2')), mark(Z))
ASEL(s(dbls(X'')), cons(Y, Z)) -> ASEL(adbls(mark(X'')), mark(Z))
ASEL(s(dbl(X'')), cons(Y, Z)) -> ASEL(adbl(mark(X'')), mark(Z))
ASEL(s(X), cons(Y, Z)) -> MARK(X)
MARK(indx(X1, X2)) -> MARK(X1)
MARK(sel(X1, X2)) -> MARK(X2)
MARK(sel(X1, X2)) -> MARK(X1)
ASEL(0, cons(X, Y)) -> MARK(X)
MARK(sel(X1, X2)) -> ASEL(mark(X1), mark(X2))
MARK(dbls(X)) -> MARK(X)
MARK(dbl(X)) -> MARK(X)
ASEL(s(X), cons(Y, Z)) -> MARK(Z)

Rules:

asel(0, cons(X, Y)) -> mark(X)
asel(s(X), cons(Y, Z)) -> asel(mark(X), mark(Z))
asel(X1, X2) -> sel(X1, X2)
aindx(nil, X) -> nil
aindx(cons(X, Y), Z) -> cons(sel(X, Z), indx(Y, Z))
aindx(X1, X2) -> indx(X1, X2)
afrom(X) -> cons(X, from(s(X)))
afrom(X) -> from(X)
mark(sel(X1, X2)) -> asel(mark(X1), mark(X2))
mark(indx(X1, X2)) -> aindx(mark(X1), X2)
mark(from(X)) -> afrom(X)
mark(0) -> 0
mark(s(X)) -> s(X)
mark(nil) -> nil
mark(cons(X1, X2)) -> cons(X1, X2)

On this DP problem, a Narrowing SCC transformation can be performed.
As a result of transforming the rule

MARK(sel(X1, X2)) -> ASEL(mark(X1), mark(X2))
18 new Dependency Pairs are created:

MARK(sel(sel(X1'', X2''), X2)) -> ASEL(asel(mark(X1''), mark(X2'')), mark(X2))
MARK(sel(indx(X1'', X2''), X2)) -> ASEL(aindx(mark(X1''), X2''), mark(X2))
MARK(sel(from(X'), X2)) -> ASEL(afrom(X'), mark(X2))
MARK(sel(0, X2)) -> ASEL(0, mark(X2))
MARK(sel(s(X'), X2)) -> ASEL(s(X'), mark(X2))
MARK(sel(nil, X2)) -> ASEL(nil, mark(X2))
MARK(sel(cons(X1'', X2''), X2)) -> ASEL(cons(X1'', X2''), mark(X2))
MARK(sel(X1, sel(X1'', X2''))) -> ASEL(mark(X1), asel(mark(X1''), mark(X2'')))
MARK(sel(X1, indx(X1'', X2''))) -> ASEL(mark(X1), aindx(mark(X1''), X2''))
MARK(sel(X1, from(X'))) -> ASEL(mark(X1), afrom(X'))
MARK(sel(X1, 0)) -> ASEL(mark(X1), 0)
MARK(sel(X1, s(X'))) -> ASEL(mark(X1), s(X'))
MARK(sel(X1, nil)) -> ASEL(mark(X1), nil)
MARK(sel(X1, cons(X1'', X2''))) -> ASEL(mark(X1), cons(X1'', X2''))

The transformation is resulting in one new DP problem:

`   R`
`     ↳DPs`
`       →DP Problem 1`
`         ↳Nar`
`           →DP Problem 2`
`             ↳Nar`
`             ...`
`               →DP Problem 3`
`                 ↳Polynomial Ordering`

Dependency Pairs:

MARK(sel(X1, cons(X1'', X2''))) -> ASEL(mark(X1), cons(X1'', X2''))
MARK(sel(X1, from(X'))) -> ASEL(mark(X1), afrom(X'))
MARK(sel(X1, indx(X1'', X2''))) -> ASEL(mark(X1), aindx(mark(X1''), X2''))
MARK(sel(X1, sel(X1'', X2''))) -> ASEL(mark(X1), asel(mark(X1''), mark(X2'')))
MARK(sel(s(X'), X2)) -> ASEL(s(X'), mark(X2))
MARK(sel(0, X2)) -> ASEL(0, mark(X2))
MARK(sel(from(X'), X2)) -> ASEL(afrom(X'), mark(X2))
MARK(sel(indx(X1'', X2''), X2)) -> ASEL(aindx(mark(X1''), X2''), mark(X2))
ASEL(s(X), cons(Y, from(X''))) -> ASEL(mark(X), afrom(X''))
ASEL(s(X), cons(Y, indx(X1', X2'))) -> ASEL(mark(X), aindx(mark(X1'), X2'))
ASEL(s(X), cons(Y, sel(X1', X2'))) -> ASEL(mark(X), asel(mark(X1'), mark(X2')))
ASEL(s(X), cons(Y, dbls(X''))) -> ASEL(mark(X), adbls(mark(X'')))
ASEL(s(X), cons(Y, dbl(X''))) -> ASEL(mark(X), adbl(mark(X'')))
ASEL(s(s(X'')), cons(Y, Z)) -> ASEL(s(X''), mark(Z))
ASEL(s(0), cons(Y, Z)) -> ASEL(0, mark(Z))
ASEL(s(from(X'')), cons(Y, Z)) -> ASEL(afrom(X''), mark(Z))
ASEL(s(indx(X1', X2')), cons(Y, Z)) -> ASEL(aindx(mark(X1'), X2'), mark(Z))
ASEL(s(sel(X1', X2')), cons(Y, Z)) -> ASEL(asel(mark(X1'), mark(X2')), mark(Z))
ASEL(s(dbls(X'')), cons(Y, Z)) -> ASEL(adbls(mark(X'')), mark(Z))
ASEL(s(dbl(X'')), cons(Y, Z)) -> ASEL(adbl(mark(X'')), mark(Z))
MARK(sel(sel(X1'', X2''), X2)) -> ASEL(asel(mark(X1''), mark(X2'')), mark(X2))
ASEL(s(X), cons(Y, Z)) -> MARK(Z)
ASEL(s(X), cons(Y, Z)) -> MARK(X)
MARK(indx(X1, X2)) -> MARK(X1)
MARK(sel(X1, X2)) -> MARK(X2)
MARK(sel(X1, X2)) -> MARK(X1)
MARK(dbls(X)) -> MARK(X)
MARK(dbl(X)) -> MARK(X)
ASEL(0, cons(X, Y)) -> MARK(X)
ASEL(s(X), cons(Y, cons(X1', X2'))) -> ASEL(mark(X), cons(X1', X2'))

Rules:

asel(0, cons(X, Y)) -> mark(X)
asel(s(X), cons(Y, Z)) -> asel(mark(X), mark(Z))
asel(X1, X2) -> sel(X1, X2)
aindx(nil, X) -> nil
aindx(cons(X, Y), Z) -> cons(sel(X, Z), indx(Y, Z))
aindx(X1, X2) -> indx(X1, X2)
afrom(X) -> cons(X, from(s(X)))
afrom(X) -> from(X)
mark(sel(X1, X2)) -> asel(mark(X1), mark(X2))
mark(indx(X1, X2)) -> aindx(mark(X1), X2)
mark(from(X)) -> afrom(X)
mark(0) -> 0
mark(s(X)) -> s(X)
mark(nil) -> nil
mark(cons(X1, X2)) -> cons(X1, X2)

The following dependency pairs can be strictly oriented:

MARK(sel(from(X'), X2)) -> ASEL(afrom(X'), mark(X2))
MARK(sel(indx(X1'', X2''), X2)) -> ASEL(aindx(mark(X1''), X2''), mark(X2))
ASEL(s(from(X'')), cons(Y, Z)) -> ASEL(afrom(X''), mark(Z))
ASEL(s(indx(X1', X2')), cons(Y, Z)) -> ASEL(aindx(mark(X1'), X2'), mark(Z))
ASEL(s(dbls(X'')), cons(Y, Z)) -> ASEL(adbls(mark(X'')), mark(Z))

Additionally, the following usable rules w.r.t. to the implicit AFS can be oriented:

asel(0, cons(X, Y)) -> mark(X)
asel(s(X), cons(Y, Z)) -> asel(mark(X), mark(Z))
asel(X1, X2) -> sel(X1, X2)
mark(sel(X1, X2)) -> asel(mark(X1), mark(X2))
mark(indx(X1, X2)) -> aindx(mark(X1), X2)
mark(from(X)) -> afrom(X)
mark(0) -> 0
mark(s(X)) -> s(X)
mark(nil) -> nil
mark(cons(X1, X2)) -> cons(X1, X2)
afrom(X) -> cons(X, from(s(X)))
afrom(X) -> from(X)
aindx(nil, X) -> nil
aindx(cons(X, Y), Z) -> cons(sel(X, Z), indx(Y, Z))
aindx(X1, X2) -> indx(X1, X2)

Used ordering: Polynomial ordering with Polynomial interpretation:
 POL(from(x1)) =  0 POL(MARK(x1)) =  1 POL(a__sel(x1, x2)) =  x1 POL(a__dbl(x1)) =  x1 POL(sel(x1, x2)) =  0 POL(mark(x1)) =  1 POL(a__from(x1)) =  0 POL(dbls(x1)) =  0 POL(0) =  1 POL(indx(x1, x2)) =  0 POL(cons(x1, x2)) =  0 POL(dbl(x1)) =  0 POL(nil) =  0 POL(a__indx(x1, x2)) =  0 POL(s(x1)) =  1 POL(a__dbls(x1)) =  0 POL(A__SEL(x1, x2)) =  x1

resulting in one new DP problem.

`   R`
`     ↳DPs`
`       →DP Problem 1`
`         ↳Nar`
`           →DP Problem 2`
`             ↳Nar`
`             ...`
`               →DP Problem 4`
`                 ↳Polynomial Ordering`

Dependency Pairs:

MARK(sel(X1, cons(X1'', X2''))) -> ASEL(mark(X1), cons(X1'', X2''))
MARK(sel(X1, from(X'))) -> ASEL(mark(X1), afrom(X'))
MARK(sel(X1, indx(X1'', X2''))) -> ASEL(mark(X1), aindx(mark(X1''), X2''))
MARK(sel(X1, sel(X1'', X2''))) -> ASEL(mark(X1), asel(mark(X1''), mark(X2'')))
MARK(sel(s(X'), X2)) -> ASEL(s(X'), mark(X2))
MARK(sel(0, X2)) -> ASEL(0, mark(X2))
ASEL(s(X), cons(Y, from(X''))) -> ASEL(mark(X), afrom(X''))
ASEL(s(X), cons(Y, indx(X1', X2'))) -> ASEL(mark(X), aindx(mark(X1'), X2'))
ASEL(s(X), cons(Y, sel(X1', X2'))) -> ASEL(mark(X), asel(mark(X1'), mark(X2')))
ASEL(s(X), cons(Y, dbls(X''))) -> ASEL(mark(X), adbls(mark(X'')))
ASEL(s(X), cons(Y, dbl(X''))) -> ASEL(mark(X), adbl(mark(X'')))
ASEL(s(s(X'')), cons(Y, Z)) -> ASEL(s(X''), mark(Z))
ASEL(s(0), cons(Y, Z)) -> ASEL(0, mark(Z))
ASEL(s(sel(X1', X2')), cons(Y, Z)) -> ASEL(asel(mark(X1'), mark(X2')), mark(Z))
ASEL(s(dbl(X'')), cons(Y, Z)) -> ASEL(adbl(mark(X'')), mark(Z))
MARK(sel(sel(X1'', X2''), X2)) -> ASEL(asel(mark(X1''), mark(X2'')), mark(X2))
ASEL(s(X), cons(Y, Z)) -> MARK(Z)
ASEL(s(X), cons(Y, Z)) -> MARK(X)
MARK(indx(X1, X2)) -> MARK(X1)
MARK(sel(X1, X2)) -> MARK(X2)
MARK(sel(X1, X2)) -> MARK(X1)
MARK(dbls(X)) -> MARK(X)
MARK(dbl(X)) -> MARK(X)
ASEL(0, cons(X, Y)) -> MARK(X)
ASEL(s(X), cons(Y, cons(X1', X2'))) -> ASEL(mark(X), cons(X1', X2'))

Rules:

asel(0, cons(X, Y)) -> mark(X)
asel(s(X), cons(Y, Z)) -> asel(mark(X), mark(Z))
asel(X1, X2) -> sel(X1, X2)
aindx(nil, X) -> nil
aindx(cons(X, Y), Z) -> cons(sel(X, Z), indx(Y, Z))
aindx(X1, X2) -> indx(X1, X2)
afrom(X) -> cons(X, from(s(X)))
afrom(X) -> from(X)
mark(sel(X1, X2)) -> asel(mark(X1), mark(X2))
mark(indx(X1, X2)) -> aindx(mark(X1), X2)
mark(from(X)) -> afrom(X)
mark(0) -> 0
mark(s(X)) -> s(X)
mark(nil) -> nil
mark(cons(X1, X2)) -> cons(X1, X2)

The following dependency pairs can be strictly oriented:

ASEL(s(X), cons(Y, dbl(X''))) -> ASEL(mark(X), adbl(mark(X'')))

Additionally, the following usable rules w.r.t. to the implicit AFS can be oriented:

asel(0, cons(X, Y)) -> mark(X)
asel(s(X), cons(Y, Z)) -> asel(mark(X), mark(Z))
asel(X1, X2) -> sel(X1, X2)
mark(sel(X1, X2)) -> asel(mark(X1), mark(X2))
mark(indx(X1, X2)) -> aindx(mark(X1), X2)
mark(from(X)) -> afrom(X)
mark(0) -> 0
mark(s(X)) -> s(X)
mark(nil) -> nil
mark(cons(X1, X2)) -> cons(X1, X2)
afrom(X) -> cons(X, from(s(X)))
afrom(X) -> from(X)
aindx(nil, X) -> nil
aindx(cons(X, Y), Z) -> cons(sel(X, Z), indx(Y, Z))
aindx(X1, X2) -> indx(X1, X2)

Used ordering: Polynomial ordering with Polynomial interpretation:
 POL(from(x1)) =  0 POL(MARK(x1)) =  1 POL(a__sel(x1, x2)) =  x2 POL(a__dbl(x1)) =  0 POL(sel(x1, x2)) =  0 POL(mark(x1)) =  1 POL(a__from(x1)) =  1 POL(dbls(x1)) =  0 POL(0) =  0 POL(indx(x1, x2)) =  0 POL(cons(x1, x2)) =  1 POL(dbl(x1)) =  0 POL(nil) =  0 POL(a__indx(x1, x2)) =  1 POL(s(x1)) =  0 POL(a__dbls(x1)) =  1 POL(A__SEL(x1, x2)) =  x2

resulting in one new DP problem.

`   R`
`     ↳DPs`
`       →DP Problem 1`
`         ↳Nar`
`           →DP Problem 2`
`             ↳Nar`
`             ...`
`               →DP Problem 5`
`                 ↳Remaining Obligation(s)`

The following remains to be proven:
Dependency Pairs:

MARK(sel(X1, cons(X1'', X2''))) -> ASEL(mark(X1), cons(X1'', X2''))
MARK(sel(X1, from(X'))) -> ASEL(mark(X1), afrom(X'))
MARK(sel(X1, indx(X1'', X2''))) -> ASEL(mark(X1), aindx(mark(X1''), X2''))
MARK(sel(X1, sel(X1'', X2''))) -> ASEL(mark(X1), asel(mark(X1''), mark(X2'')))
MARK(sel(s(X'), X2)) -> ASEL(s(X'), mark(X2))
MARK(sel(0, X2)) -> ASEL(0, mark(X2))
ASEL(s(X), cons(Y, from(X''))) -> ASEL(mark(X), afrom(X''))
ASEL(s(X), cons(Y, indx(X1', X2'))) -> ASEL(mark(X), aindx(mark(X1'), X2'))
ASEL(s(X), cons(Y, sel(X1', X2'))) -> ASEL(mark(X), asel(mark(X1'), mark(X2')))
ASEL(s(X), cons(Y, dbls(X''))) -> ASEL(mark(X), adbls(mark(X'')))
ASEL(s(s(X'')), cons(Y, Z)) -> ASEL(s(X''), mark(Z))
ASEL(s(0), cons(Y, Z)) -> ASEL(0, mark(Z))
ASEL(s(sel(X1', X2')), cons(Y, Z)) -> ASEL(asel(mark(X1'), mark(X2')), mark(Z))
ASEL(s(dbl(X'')), cons(Y, Z)) -> ASEL(adbl(mark(X'')), mark(Z))
MARK(sel(sel(X1'', X2''), X2)) -> ASEL(asel(mark(X1''), mark(X2'')), mark(X2))
ASEL(s(X), cons(Y, Z)) -> MARK(Z)
ASEL(s(X), cons(Y, Z)) -> MARK(X)
MARK(indx(X1, X2)) -> MARK(X1)
MARK(sel(X1, X2)) -> MARK(X2)
MARK(sel(X1, X2)) -> MARK(X1)
MARK(dbls(X)) -> MARK(X)
MARK(dbl(X)) -> MARK(X)
ASEL(0, cons(X, Y)) -> MARK(X)
ASEL(s(X), cons(Y, cons(X1', X2'))) -> ASEL(mark(X), cons(X1', X2'))

Rules:

asel(0, cons(X, Y)) -> mark(X)
asel(s(X), cons(Y, Z)) -> asel(mark(X), mark(Z))
asel(X1, X2) -> sel(X1, X2)
aindx(nil, X) -> nil
aindx(cons(X, Y), Z) -> cons(sel(X, Z), indx(Y, Z))
aindx(X1, X2) -> indx(X1, X2)
afrom(X) -> cons(X, from(s(X)))
afrom(X) -> from(X)
mark(sel(X1, X2)) -> asel(mark(X1), mark(X2))
mark(indx(X1, X2)) -> aindx(mark(X1), X2)
mark(from(X)) -> afrom(X)
mark(0) -> 0
mark(s(X)) -> s(X)
mark(nil) -> nil
mark(cons(X1, X2)) -> cons(X1, X2)

Termination of R could not be shown.
Duration:
0:24 minutes