(0) Obligation:

The Runtime Complexity (innermost) of the given CpxTRS could be proven to be BOUNDS(1, n^1).


The TRS R consists of the following rules:

f(0) → s(0)
f(s(0)) → s(s(0))
f(s(0)) → *(s(s(0)), f(0))
f(+(x, s(0))) → +(s(s(0)), f(x))
f(+(x, y)) → *(f(x), f(y))

Rewrite Strategy: INNERMOST

(1) TrsToWeightedTrsProof (BOTH BOUNDS(ID, ID) transformation)

Transformed TRS to weighted TRS

(2) Obligation:

The Runtime Complexity (innermost) of the given CpxWeightedTrs could be proven to be BOUNDS(1, n^1).


The TRS R consists of the following rules:

f(0) → s(0) [1]
f(s(0)) → s(s(0)) [1]
f(s(0)) → *(s(s(0)), f(0)) [1]
f(+(x, s(0))) → +(s(s(0)), f(x)) [1]
f(+(x, y)) → *(f(x), f(y)) [1]

Rewrite Strategy: INNERMOST

(3) TypeInferenceProof (BOTH BOUNDS(ID, ID) transformation)

Infered types.

(4) Obligation:

Runtime Complexity Weighted TRS with Types.
The TRS R consists of the following rules:

f(0) → s(0) [1]
f(s(0)) → s(s(0)) [1]
f(s(0)) → *(s(s(0)), f(0)) [1]
f(+(x, s(0))) → +(s(s(0)), f(x)) [1]
f(+(x, y)) → *(f(x), f(y)) [1]

The TRS has the following type information:
f :: 0:s:*:+ → 0:s:*:+
0 :: 0:s:*:+
s :: 0:s:*:+ → 0:s:*:+
* :: 0:s:*:+ → 0:s:*:+ → 0:s:*:+
+ :: 0:s:*:+ → 0:s:*:+ → 0:s:*:+

Rewrite Strategy: INNERMOST

(5) CompletionProof (UPPER BOUND(ID) transformation)

The transformation into a RNTS is sound, since:

(a) The obligation is a constructor system where every type has a constant constructor,

(b) The following defined symbols do not have to be completely defined, as they can never occur inside other defined symbols:


f

(c) The following functions are completely defined:
none

Due to the following rules being added:
none

And the following fresh constants: none

(6) Obligation:

Runtime Complexity Weighted TRS where critical functions are completely defined. The underlying TRS is:

Runtime Complexity Weighted TRS with Types.
The TRS R consists of the following rules:

f(0) → s(0) [1]
f(s(0)) → s(s(0)) [1]
f(s(0)) → *(s(s(0)), f(0)) [1]
f(+(x, s(0))) → +(s(s(0)), f(x)) [1]
f(+(x, y)) → *(f(x), f(y)) [1]

The TRS has the following type information:
f :: 0:s:*:+ → 0:s:*:+
0 :: 0:s:*:+
s :: 0:s:*:+ → 0:s:*:+
* :: 0:s:*:+ → 0:s:*:+ → 0:s:*:+
+ :: 0:s:*:+ → 0:s:*:+ → 0:s:*:+

Rewrite Strategy: INNERMOST

(7) NarrowingProof (BOTH BOUNDS(ID, ID) transformation)

Narrowed the inner basic terms of all right-hand sides by a single narrowing step.

(8) Obligation:

Runtime Complexity Weighted TRS where critical functions are completely defined. The underlying TRS is:

Runtime Complexity Weighted TRS with Types.
The TRS R consists of the following rules:

f(0) → s(0) [1]
f(s(0)) → s(s(0)) [1]
f(s(0)) → *(s(s(0)), f(0)) [1]
f(+(x, s(0))) → +(s(s(0)), f(x)) [1]
f(+(x, y)) → *(f(x), f(y)) [1]

The TRS has the following type information:
f :: 0:s:*:+ → 0:s:*:+
0 :: 0:s:*:+
s :: 0:s:*:+ → 0:s:*:+
* :: 0:s:*:+ → 0:s:*:+ → 0:s:*:+
+ :: 0:s:*:+ → 0:s:*:+ → 0:s:*:+

Rewrite Strategy: INNERMOST

(9) CpxTypedWeightedTrsToRntsProof (UPPER BOUND(ID) transformation)

Transformed the TRS into an over-approximating RNTS by (improved) Size Abstraction.
The constant constructors are abstracted as follows:

0 => 0

(10) Obligation:

Complexity RNTS consisting of the following rules:

f(z) -{ 1 }→ 1 + 0 :|: z = 0
f(z) -{ 1 }→ 1 + (1 + 0) :|: z = 1 + 0
f(z) -{ 1 }→ 1 + f(x) + f(y) :|: z = 1 + x + y, x >= 0, y >= 0
f(z) -{ 1 }→ 1 + (1 + (1 + 0)) + f(x) :|: x >= 0, z = 1 + x + (1 + 0)
f(z) -{ 1 }→ 1 + (1 + (1 + 0)) + f(0) :|: z = 1 + 0

(11) SimplificationProof (BOTH BOUNDS(ID, ID) transformation)

Simplified the RNTS by moving equalities from the constraints into the right-hand sides.

(12) Obligation:

Complexity RNTS consisting of the following rules:

f(z) -{ 1 }→ 1 + 0 :|: z = 0
f(z) -{ 1 }→ 1 + (1 + 0) :|: z = 1 + 0
f(z) -{ 1 }→ 1 + f(x) + f(y) :|: z = 1 + x + y, x >= 0, y >= 0
f(z) -{ 1 }→ 1 + (1 + (1 + 0)) + f(0) :|: z = 1 + 0
f(z) -{ 1 }→ 1 + (1 + (1 + 0)) + f(z - 2) :|: z - 2 >= 0

(13) CpxRntsAnalysisOrderProof (BOTH BOUNDS(ID, ID) transformation)

Found the following analysis order by SCC decomposition:

{ f }

(14) Obligation:

Complexity RNTS consisting of the following rules:

f(z) -{ 1 }→ 1 + 0 :|: z = 0
f(z) -{ 1 }→ 1 + (1 + 0) :|: z = 1 + 0
f(z) -{ 1 }→ 1 + f(x) + f(y) :|: z = 1 + x + y, x >= 0, y >= 0
f(z) -{ 1 }→ 1 + (1 + (1 + 0)) + f(0) :|: z = 1 + 0
f(z) -{ 1 }→ 1 + (1 + (1 + 0)) + f(z - 2) :|: z - 2 >= 0

Function symbols to be analyzed: {f}

(15) IntTrsBoundProof (UPPER BOUND(ID) transformation)


Computed SIZE bound using CoFloCo for: f
after applying outer abstraction to obtain an ITS,
resulting in: O(n1) with polynomial bound: 4 + 4·z

(16) Obligation:

Complexity RNTS consisting of the following rules:

f(z) -{ 1 }→ 1 + 0 :|: z = 0
f(z) -{ 1 }→ 1 + (1 + 0) :|: z = 1 + 0
f(z) -{ 1 }→ 1 + f(x) + f(y) :|: z = 1 + x + y, x >= 0, y >= 0
f(z) -{ 1 }→ 1 + (1 + (1 + 0)) + f(0) :|: z = 1 + 0
f(z) -{ 1 }→ 1 + (1 + (1 + 0)) + f(z - 2) :|: z - 2 >= 0

Function symbols to be analyzed: {f}
Previous analysis results are:
f: runtime: ?, size: O(n1) [4 + 4·z]

(17) IntTrsBoundProof (UPPER BOUND(ID) transformation)


Computed RUNTIME bound using CoFloCo for: f
after applying outer abstraction to obtain an ITS,
resulting in: O(n1) with polynomial bound: 2 + 3·z

(18) Obligation:

Complexity RNTS consisting of the following rules:

f(z) -{ 1 }→ 1 + 0 :|: z = 0
f(z) -{ 1 }→ 1 + (1 + 0) :|: z = 1 + 0
f(z) -{ 1 }→ 1 + f(x) + f(y) :|: z = 1 + x + y, x >= 0, y >= 0
f(z) -{ 1 }→ 1 + (1 + (1 + 0)) + f(0) :|: z = 1 + 0
f(z) -{ 1 }→ 1 + (1 + (1 + 0)) + f(z - 2) :|: z - 2 >= 0

Function symbols to be analyzed:
Previous analysis results are:
f: runtime: O(n1) [2 + 3·z], size: O(n1) [4 + 4·z]

(19) FinalProof (EQUIVALENT transformation)

Computed overall runtime complexity

(20) BOUNDS(1, n^1)