(0) Obligation:

Runtime Complexity Relative TRS:
The TRS R consists of the following rules:

f(C(x1, x2)) → C(f(x1), f(x2))
f(Z) → Z
eqZList(C(x1, x2), C(y1, y2)) → and(eqZList(x1, y1), eqZList(x2, y2))
eqZList(C(x1, x2), Z) → False
eqZList(Z, C(y1, y2)) → False
eqZList(Z, Z) → True
second(C(x1, x2)) → x2
first(C(x1, x2)) → x1
g(x) → x

The (relative) TRS S consists of the following rules:

and(False, False) → False
and(True, False) → False
and(False, True) → False
and(True, True) → True

Rewrite Strategy: INNERMOST

(1) DecreasingLoopProof (EQUIVALENT transformation)

The following loop(s) give(s) rise to the lower bound Ω(n1):
The rewrite sequence
f(C(x1, x2)) →+ C(f(x1), f(x2))
gives rise to a decreasing loop by considering the right hand sides subterm at position [0].
The pumping substitution is [x1 / C(x1, x2)].
The result substitution is [ ].

(2) BOUNDS(n^1, INF)