(0) Obligation:

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

a__zeroscons(0, zeros)
a__tail(cons(X, XS)) → mark(XS)
mark(zeros) → a__zeros
mark(tail(X)) → a__tail(mark(X))
mark(cons(X1, X2)) → cons(mark(X1), X2)
mark(0) → 0
a__zeroszeros
a__tail(X) → tail(X)

Q is empty.

(1) QTRSRRRProof (EQUIVALENT transformation)

Used ordering:
Polynomial interpretation [POLO]:

POL(0) = 0   
POL(a__tail(x1)) = 3 + x1   
POL(a__zeros) = 1   
POL(cons(x1, x2)) = x1 + x2   
POL(mark(x1)) = 2 + x1   
POL(tail(x1)) = 3 + x1   
POL(zeros) = 0   
With this ordering the following rules can be removed by the rule removal processor [LPAR04] because they are oriented strictly:

a__zeroscons(0, zeros)
a__tail(cons(X, XS)) → mark(XS)
mark(zeros) → a__zeros
mark(0) → 0
a__zeroszeros


(2) Obligation:

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

mark(tail(X)) → a__tail(mark(X))
mark(cons(X1, X2)) → cons(mark(X1), X2)
a__tail(X) → tail(X)

Q is empty.

(3) QTRSRRRProof (EQUIVALENT transformation)

Used ordering:
Polynomial interpretation [POLO]:

POL(a__tail(x1)) = 2 + x1   
POL(cons(x1, x2)) = 1 + x1 + x2   
POL(mark(x1)) = 2 + 2·x1   
POL(tail(x1)) = 1 + x1   
With this ordering the following rules can be removed by the rule removal processor [LPAR04] because they are oriented strictly:

mark(cons(X1, X2)) → cons(mark(X1), X2)
a__tail(X) → tail(X)


(4) Obligation:

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

mark(tail(X)) → a__tail(mark(X))

Q is empty.

(5) QTRSRRRProof (EQUIVALENT transformation)

Used ordering:
Polynomial interpretation [POLO]:

POL(a__tail(x1)) = x1   
POL(mark(x1)) = x1   
POL(tail(x1)) = 1 + x1   
With this ordering the following rules can be removed by the rule removal processor [LPAR04] because they are oriented strictly:

mark(tail(X)) → a__tail(mark(X))


(6) Obligation:

Q restricted rewrite system:
R is empty.
Q is empty.

(7) RisEmptyProof (EQUIVALENT transformation)

The TRS R is empty. Hence, termination is trivially proven.

(8) TRUE