(0) Obligation:
Runtime Complexity TRS:
The TRS R consists of the following rules:
cond(true, x) → cond(and(even(x), gr(x, 0)), p(x))
and(x, false) → false
and(false, x) → false
and(true, true) → true
even(0) → true
even(s(0)) → false
even(s(s(x))) → even(x)
gr(0, x) → false
gr(s(x), 0) → true
gr(s(x), s(y)) → gr(x, y)
p(0) → 0
p(s(x)) → x
Rewrite Strategy: FULL
(1) DecreasingLoopProof (EQUIVALENT transformation)
The following loop(s) give(s) rise to the lower bound Ω(n1):
The rewrite sequence
even(s(s(x))) →+ even(x)
gives rise to a decreasing loop by considering the right hand sides subterm at position [].
The pumping substitution is [x / s(s(x))].
The result substitution is [ ].
(2) BOUNDS(n^1, INF)
(3) RenamingProof (EQUIVALENT transformation)
Renamed function symbols to avoid clashes with predefined symbol.
(4) Obligation:
Runtime Complexity Relative TRS:
The TRS R consists of the following rules:
cond(true, x) → cond(and(even(x), gr(x, 0')), p(x))
and(x, false) → false
and(false, x) → false
and(true, true) → true
even(0') → true
even(s(0')) → false
even(s(s(x))) → even(x)
gr(0', x) → false
gr(s(x), 0') → true
gr(s(x), s(y)) → gr(x, y)
p(0') → 0'
p(s(x)) → x
S is empty.
Rewrite Strategy: FULL
(5) TypeInferenceProof (BOTH BOUNDS(ID, ID) transformation)
Infered types.
(6) Obligation:
TRS:
Rules:
cond(true, x) → cond(and(even(x), gr(x, 0')), p(x))
and(x, false) → false
and(false, x) → false
and(true, true) → true
even(0') → true
even(s(0')) → false
even(s(s(x))) → even(x)
gr(0', x) → false
gr(s(x), 0') → true
gr(s(x), s(y)) → gr(x, y)
p(0') → 0'
p(s(x)) → x
Types:
cond :: true:false → 0':s:y → cond
true :: true:false
and :: true:false → true:false → true:false
even :: 0':s:y → true:false
gr :: 0':s:y → 0':s:y → true:false
0' :: 0':s:y
p :: 0':s:y → 0':s:y
false :: true:false
s :: 0':s:y → 0':s:y
y :: 0':s:y
hole_cond1_0 :: cond
hole_true:false2_0 :: true:false
hole_0':s:y3_0 :: 0':s:y
gen_0':s:y4_0 :: Nat → 0':s:y
(7) OrderProof (LOWER BOUND(ID) transformation)
Heuristically decided to analyse the following defined symbols:
cond,
even,
grThey will be analysed ascendingly in the following order:
even < cond
gr < cond
(8) Obligation:
TRS:
Rules:
cond(
true,
x) →
cond(
and(
even(
x),
gr(
x,
0')),
p(
x))
and(
x,
false) →
falseand(
false,
x) →
falseand(
true,
true) →
trueeven(
0') →
trueeven(
s(
0')) →
falseeven(
s(
s(
x))) →
even(
x)
gr(
0',
x) →
falsegr(
s(
x),
0') →
truegr(
s(
x),
s(
y)) →
gr(
x,
y)
p(
0') →
0'p(
s(
x)) →
xTypes:
cond :: true:false → 0':s:y → cond
true :: true:false
and :: true:false → true:false → true:false
even :: 0':s:y → true:false
gr :: 0':s:y → 0':s:y → true:false
0' :: 0':s:y
p :: 0':s:y → 0':s:y
false :: true:false
s :: 0':s:y → 0':s:y
y :: 0':s:y
hole_cond1_0 :: cond
hole_true:false2_0 :: true:false
hole_0':s:y3_0 :: 0':s:y
gen_0':s:y4_0 :: Nat → 0':s:y
Generator Equations:
gen_0':s:y4_0(0) ⇔ 0'
gen_0':s:y4_0(+(x, 1)) ⇔ s(gen_0':s:y4_0(x))
The following defined symbols remain to be analysed:
even, cond, gr
They will be analysed ascendingly in the following order:
even < cond
gr < cond
(9) RewriteLemmaProof (LOWER BOUND(ID) transformation)
Proved the following rewrite lemma:
even(
gen_0':s:y4_0(
*(
2,
n6_0))) →
true, rt ∈ Ω(1 + n6
0)
Induction Base:
even(gen_0':s:y4_0(*(2, 0))) →RΩ(1)
true
Induction Step:
even(gen_0':s:y4_0(*(2, +(n6_0, 1)))) →RΩ(1)
even(gen_0':s:y4_0(*(2, n6_0))) →IH
true
We have rt ∈ Ω(n1) and sz ∈ O(n). Thus, we have ircR ∈ Ω(n).
(10) Complex Obligation (BEST)
(11) Obligation:
TRS:
Rules:
cond(
true,
x) →
cond(
and(
even(
x),
gr(
x,
0')),
p(
x))
and(
x,
false) →
falseand(
false,
x) →
falseand(
true,
true) →
trueeven(
0') →
trueeven(
s(
0')) →
falseeven(
s(
s(
x))) →
even(
x)
gr(
0',
x) →
falsegr(
s(
x),
0') →
truegr(
s(
x),
s(
y)) →
gr(
x,
y)
p(
0') →
0'p(
s(
x)) →
xTypes:
cond :: true:false → 0':s:y → cond
true :: true:false
and :: true:false → true:false → true:false
even :: 0':s:y → true:false
gr :: 0':s:y → 0':s:y → true:false
0' :: 0':s:y
p :: 0':s:y → 0':s:y
false :: true:false
s :: 0':s:y → 0':s:y
y :: 0':s:y
hole_cond1_0 :: cond
hole_true:false2_0 :: true:false
hole_0':s:y3_0 :: 0':s:y
gen_0':s:y4_0 :: Nat → 0':s:y
Lemmas:
even(gen_0':s:y4_0(*(2, n6_0))) → true, rt ∈ Ω(1 + n60)
Generator Equations:
gen_0':s:y4_0(0) ⇔ 0'
gen_0':s:y4_0(+(x, 1)) ⇔ s(gen_0':s:y4_0(x))
The following defined symbols remain to be analysed:
gr, cond
They will be analysed ascendingly in the following order:
gr < cond
(12) NoRewriteLemmaProof (LOWER BOUND(ID) transformation)
Could not prove a rewrite lemma for the defined symbol gr.
(13) Obligation:
TRS:
Rules:
cond(
true,
x) →
cond(
and(
even(
x),
gr(
x,
0')),
p(
x))
and(
x,
false) →
falseand(
false,
x) →
falseand(
true,
true) →
trueeven(
0') →
trueeven(
s(
0')) →
falseeven(
s(
s(
x))) →
even(
x)
gr(
0',
x) →
falsegr(
s(
x),
0') →
truegr(
s(
x),
s(
y)) →
gr(
x,
y)
p(
0') →
0'p(
s(
x)) →
xTypes:
cond :: true:false → 0':s:y → cond
true :: true:false
and :: true:false → true:false → true:false
even :: 0':s:y → true:false
gr :: 0':s:y → 0':s:y → true:false
0' :: 0':s:y
p :: 0':s:y → 0':s:y
false :: true:false
s :: 0':s:y → 0':s:y
y :: 0':s:y
hole_cond1_0 :: cond
hole_true:false2_0 :: true:false
hole_0':s:y3_0 :: 0':s:y
gen_0':s:y4_0 :: Nat → 0':s:y
Lemmas:
even(gen_0':s:y4_0(*(2, n6_0))) → true, rt ∈ Ω(1 + n60)
Generator Equations:
gen_0':s:y4_0(0) ⇔ 0'
gen_0':s:y4_0(+(x, 1)) ⇔ s(gen_0':s:y4_0(x))
The following defined symbols remain to be analysed:
cond
(14) NoRewriteLemmaProof (LOWER BOUND(ID) transformation)
Could not prove a rewrite lemma for the defined symbol cond.
(15) Obligation:
TRS:
Rules:
cond(
true,
x) →
cond(
and(
even(
x),
gr(
x,
0')),
p(
x))
and(
x,
false) →
falseand(
false,
x) →
falseand(
true,
true) →
trueeven(
0') →
trueeven(
s(
0')) →
falseeven(
s(
s(
x))) →
even(
x)
gr(
0',
x) →
falsegr(
s(
x),
0') →
truegr(
s(
x),
s(
y)) →
gr(
x,
y)
p(
0') →
0'p(
s(
x)) →
xTypes:
cond :: true:false → 0':s:y → cond
true :: true:false
and :: true:false → true:false → true:false
even :: 0':s:y → true:false
gr :: 0':s:y → 0':s:y → true:false
0' :: 0':s:y
p :: 0':s:y → 0':s:y
false :: true:false
s :: 0':s:y → 0':s:y
y :: 0':s:y
hole_cond1_0 :: cond
hole_true:false2_0 :: true:false
hole_0':s:y3_0 :: 0':s:y
gen_0':s:y4_0 :: Nat → 0':s:y
Lemmas:
even(gen_0':s:y4_0(*(2, n6_0))) → true, rt ∈ Ω(1 + n60)
Generator Equations:
gen_0':s:y4_0(0) ⇔ 0'
gen_0':s:y4_0(+(x, 1)) ⇔ s(gen_0':s:y4_0(x))
No more defined symbols left to analyse.
(16) LowerBoundsProof (EQUIVALENT transformation)
The lowerbound Ω(n1) was proven with the following lemma:
even(gen_0':s:y4_0(*(2, n6_0))) → true, rt ∈ Ω(1 + n60)
(17) BOUNDS(n^1, INF)
(18) Obligation:
TRS:
Rules:
cond(
true,
x) →
cond(
and(
even(
x),
gr(
x,
0')),
p(
x))
and(
x,
false) →
falseand(
false,
x) →
falseand(
true,
true) →
trueeven(
0') →
trueeven(
s(
0')) →
falseeven(
s(
s(
x))) →
even(
x)
gr(
0',
x) →
falsegr(
s(
x),
0') →
truegr(
s(
x),
s(
y)) →
gr(
x,
y)
p(
0') →
0'p(
s(
x)) →
xTypes:
cond :: true:false → 0':s:y → cond
true :: true:false
and :: true:false → true:false → true:false
even :: 0':s:y → true:false
gr :: 0':s:y → 0':s:y → true:false
0' :: 0':s:y
p :: 0':s:y → 0':s:y
false :: true:false
s :: 0':s:y → 0':s:y
y :: 0':s:y
hole_cond1_0 :: cond
hole_true:false2_0 :: true:false
hole_0':s:y3_0 :: 0':s:y
gen_0':s:y4_0 :: Nat → 0':s:y
Lemmas:
even(gen_0':s:y4_0(*(2, n6_0))) → true, rt ∈ Ω(1 + n60)
Generator Equations:
gen_0':s:y4_0(0) ⇔ 0'
gen_0':s:y4_0(+(x, 1)) ⇔ s(gen_0':s:y4_0(x))
No more defined symbols left to analyse.
(19) LowerBoundsProof (EQUIVALENT transformation)
The lowerbound Ω(n1) was proven with the following lemma:
even(gen_0':s:y4_0(*(2, n6_0))) → true, rt ∈ Ω(1 + n60)
(20) BOUNDS(n^1, INF)