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

le(0, y) → true
le(s(x), 0) → false
le(s(x), s(y)) → le(x, y)
int(x, y) → if(le(x, y), x, y)
if(true, x, y) → cons(x, int(s(x), y))
if(false, x, y) → nil

Rewrite Strategy: INNERMOST

Renamed function symbols to avoid clashes with predefined symbol.

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

le'(0', y) → true'
le'(s'(x), 0') → false'
le'(s'(x), s'(y)) → le'(x, y)
int'(x, y) → if'(le'(x, y), x, y)
if'(true', x, y) → cons'(x, int'(s'(x), y))
if'(false', x, y) → nil'

Rewrite Strategy: INNERMOST

Sliced the following arguments:
cons'/0

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

le'(0', y) → true'
le'(s'(x), 0') → false'
le'(s'(x), s'(y)) → le'(x, y)
int'(x, y) → if'(le'(x, y), x, y)
if'(true', x, y) → cons'(int'(s'(x), y))
if'(false', x, y) → nil'

Rewrite Strategy: INNERMOST

Infered types.

Rules:
le'(0', y) → true'
le'(s'(x), 0') → false'
le'(s'(x), s'(y)) → le'(x, y)
int'(x, y) → if'(le'(x, y), x, y)
if'(true', x, y) → cons'(int'(s'(x), y))
if'(false', x, y) → nil'

Types:
le' :: 0':s' → 0':s' → true':false'
0' :: 0':s'
true' :: true':false'
s' :: 0':s' → 0':s'
false' :: true':false'
int' :: 0':s' → 0':s' → cons':nil'
if' :: true':false' → 0':s' → 0':s' → cons':nil'
cons' :: cons':nil' → cons':nil'
nil' :: cons':nil'
_hole_true':false'1 :: true':false'
_hole_0':s'2 :: 0':s'
_hole_cons':nil'3 :: cons':nil'
_gen_0':s'4 :: Nat → 0':s'
_gen_cons':nil'5 :: Nat → cons':nil'

Heuristically decided to analyse the following defined symbols:
le', int'

They will be analysed ascendingly in the following order:
le' < int'

Rules:
le'(0', y) → true'
le'(s'(x), 0') → false'
le'(s'(x), s'(y)) → le'(x, y)
int'(x, y) → if'(le'(x, y), x, y)
if'(true', x, y) → cons'(int'(s'(x), y))
if'(false', x, y) → nil'

Types:
le' :: 0':s' → 0':s' → true':false'
0' :: 0':s'
true' :: true':false'
s' :: 0':s' → 0':s'
false' :: true':false'
int' :: 0':s' → 0':s' → cons':nil'
if' :: true':false' → 0':s' → 0':s' → cons':nil'
cons' :: cons':nil' → cons':nil'
nil' :: cons':nil'
_hole_true':false'1 :: true':false'
_hole_0':s'2 :: 0':s'
_hole_cons':nil'3 :: cons':nil'
_gen_0':s'4 :: Nat → 0':s'
_gen_cons':nil'5 :: Nat → cons':nil'

Generator Equations:
_gen_0':s'4(0) ⇔ 0'
_gen_0':s'4(+(x, 1)) ⇔ s'(_gen_0':s'4(x))
_gen_cons':nil'5(0) ⇔ nil'
_gen_cons':nil'5(+(x, 1)) ⇔ cons'(_gen_cons':nil'5(x))

The following defined symbols remain to be analysed:
le', int'

They will be analysed ascendingly in the following order:
le' < int'

Proved the following rewrite lemma:
le'(_gen_0':s'4(_n7), _gen_0':s'4(_n7)) → true', rt ∈ Ω(1 + n7)

Induction Base:
le'(_gen_0':s'4(0), _gen_0':s'4(0)) →RΩ(1)
true'

Induction Step:
le'(_gen_0':s'4(+(_\$n8, 1)), _gen_0':s'4(+(_\$n8, 1))) →RΩ(1)
le'(_gen_0':s'4(_\$n8), _gen_0':s'4(_\$n8)) →IH
true'

We have rt ∈ Ω(n) and sz ∈ O(n). Thus, we have ircR ∈ Ω(n).

Rules:
le'(0', y) → true'
le'(s'(x), 0') → false'
le'(s'(x), s'(y)) → le'(x, y)
int'(x, y) → if'(le'(x, y), x, y)
if'(true', x, y) → cons'(int'(s'(x), y))
if'(false', x, y) → nil'

Types:
le' :: 0':s' → 0':s' → true':false'
0' :: 0':s'
true' :: true':false'
s' :: 0':s' → 0':s'
false' :: true':false'
int' :: 0':s' → 0':s' → cons':nil'
if' :: true':false' → 0':s' → 0':s' → cons':nil'
cons' :: cons':nil' → cons':nil'
nil' :: cons':nil'
_hole_true':false'1 :: true':false'
_hole_0':s'2 :: 0':s'
_hole_cons':nil'3 :: cons':nil'
_gen_0':s'4 :: Nat → 0':s'
_gen_cons':nil'5 :: Nat → cons':nil'

Lemmas:
le'(_gen_0':s'4(_n7), _gen_0':s'4(_n7)) → true', rt ∈ Ω(1 + n7)

Generator Equations:
_gen_0':s'4(0) ⇔ 0'
_gen_0':s'4(+(x, 1)) ⇔ s'(_gen_0':s'4(x))
_gen_cons':nil'5(0) ⇔ nil'
_gen_cons':nil'5(+(x, 1)) ⇔ cons'(_gen_cons':nil'5(x))

The following defined symbols remain to be analysed:
int'

Could not prove a rewrite lemma for the defined symbol int'.

Rules:
le'(0', y) → true'
le'(s'(x), 0') → false'
le'(s'(x), s'(y)) → le'(x, y)
int'(x, y) → if'(le'(x, y), x, y)
if'(true', x, y) → cons'(int'(s'(x), y))
if'(false', x, y) → nil'

Types:
le' :: 0':s' → 0':s' → true':false'
0' :: 0':s'
true' :: true':false'
s' :: 0':s' → 0':s'
false' :: true':false'
int' :: 0':s' → 0':s' → cons':nil'
if' :: true':false' → 0':s' → 0':s' → cons':nil'
cons' :: cons':nil' → cons':nil'
nil' :: cons':nil'
_hole_true':false'1 :: true':false'
_hole_0':s'2 :: 0':s'
_hole_cons':nil'3 :: cons':nil'
_gen_0':s'4 :: Nat → 0':s'
_gen_cons':nil'5 :: Nat → cons':nil'

Lemmas:
le'(_gen_0':s'4(_n7), _gen_0':s'4(_n7)) → true', rt ∈ Ω(1 + n7)

Generator Equations:
_gen_0':s'4(0) ⇔ 0'
_gen_0':s'4(+(x, 1)) ⇔ s'(_gen_0':s'4(x))
_gen_cons':nil'5(0) ⇔ nil'
_gen_cons':nil'5(+(x, 1)) ⇔ cons'(_gen_cons':nil'5(x))

No more defined symbols left to analyse.

The lowerbound Ω(n) was proven with the following lemma:
le'(_gen_0':s'4(_n7), _gen_0':s'4(_n7)) → true', rt ∈ Ω(1 + n7)