(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:

duplicate(Cons(x, xs)) → Cons(x, Cons(x, duplicate(xs)))
duplicate(Nil) → Nil
goal(x) → duplicate(x)

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:

duplicate(Cons(x, xs)) → Cons(x, Cons(x, duplicate(xs))) [1]
duplicate(Nil) → Nil [1]
goal(x) → duplicate(x) [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:

duplicate(Cons(x, xs)) → Cons(x, Cons(x, duplicate(xs))) [1]
duplicate(Nil) → Nil [1]
goal(x) → duplicate(x) [1]

The TRS has the following type information:
duplicate :: Cons:Nil → Cons:Nil
Cons :: a → Cons:Nil → Cons:Nil
Nil :: Cons:Nil
goal :: Cons:Nil → Cons:Nil

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:


duplicate
goal

(c) The following functions are completely defined:
none

Due to the following rules being added:
none

And the following fresh constants:

const

(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:

duplicate(Cons(x, xs)) → Cons(x, Cons(x, duplicate(xs))) [1]
duplicate(Nil) → Nil [1]
goal(x) → duplicate(x) [1]

The TRS has the following type information:
duplicate :: Cons:Nil → Cons:Nil
Cons :: a → Cons:Nil → Cons:Nil
Nil :: Cons:Nil
goal :: Cons:Nil → Cons:Nil
const :: a

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:

duplicate(Cons(x, xs)) → Cons(x, Cons(x, duplicate(xs))) [1]
duplicate(Nil) → Nil [1]
goal(x) → duplicate(x) [1]

The TRS has the following type information:
duplicate :: Cons:Nil → Cons:Nil
Cons :: a → Cons:Nil → Cons:Nil
Nil :: Cons:Nil
goal :: Cons:Nil → Cons:Nil
const :: a

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:

Nil => 0
const => 0

(10) Obligation:

Complexity RNTS consisting of the following rules:

duplicate(z) -{ 1 }→ 0 :|: z = 0
duplicate(z) -{ 1 }→ 1 + x + (1 + x + duplicate(xs)) :|: z = 1 + x + xs, xs >= 0, x >= 0
goal(z) -{ 1 }→ duplicate(x) :|: x >= 0, z = x

(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:

duplicate(z) -{ 1 }→ 0 :|: z = 0
duplicate(z) -{ 1 }→ 1 + x + (1 + x + duplicate(xs)) :|: z = 1 + x + xs, xs >= 0, x >= 0
goal(z) -{ 1 }→ duplicate(z) :|: z >= 0

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

Found the following analysis order by SCC decomposition:

{ duplicate }
{ goal }

(14) Obligation:

Complexity RNTS consisting of the following rules:

duplicate(z) -{ 1 }→ 0 :|: z = 0
duplicate(z) -{ 1 }→ 1 + x + (1 + x + duplicate(xs)) :|: z = 1 + x + xs, xs >= 0, x >= 0
goal(z) -{ 1 }→ duplicate(z) :|: z >= 0

Function symbols to be analyzed: {duplicate}, {goal}

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


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

(16) Obligation:

Complexity RNTS consisting of the following rules:

duplicate(z) -{ 1 }→ 0 :|: z = 0
duplicate(z) -{ 1 }→ 1 + x + (1 + x + duplicate(xs)) :|: z = 1 + x + xs, xs >= 0, x >= 0
goal(z) -{ 1 }→ duplicate(z) :|: z >= 0

Function symbols to be analyzed: {duplicate}, {goal}
Previous analysis results are:
duplicate: runtime: ?, size: O(n1) [2·z]

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


Computed RUNTIME bound using CoFloCo for: duplicate
after applying outer abstraction to obtain an ITS,
resulting in: O(n1) with polynomial bound: 1 + z

(18) Obligation:

Complexity RNTS consisting of the following rules:

duplicate(z) -{ 1 }→ 0 :|: z = 0
duplicate(z) -{ 1 }→ 1 + x + (1 + x + duplicate(xs)) :|: z = 1 + x + xs, xs >= 0, x >= 0
goal(z) -{ 1 }→ duplicate(z) :|: z >= 0

Function symbols to be analyzed: {goal}
Previous analysis results are:
duplicate: runtime: O(n1) [1 + z], size: O(n1) [2·z]

(19) ResultPropagationProof (UPPER BOUND(ID) transformation)

Applied inner abstraction using the recently inferred runtime/size bounds where possible.

(20) Obligation:

Complexity RNTS consisting of the following rules:

duplicate(z) -{ 1 }→ 0 :|: z = 0
duplicate(z) -{ 2 + xs }→ 1 + x + (1 + x + s) :|: s >= 0, s <= 2 * xs, z = 1 + x + xs, xs >= 0, x >= 0
goal(z) -{ 2 + z }→ s' :|: s' >= 0, s' <= 2 * z, z >= 0

Function symbols to be analyzed: {goal}
Previous analysis results are:
duplicate: runtime: O(n1) [1 + z], size: O(n1) [2·z]

(21) IntTrsBoundProof (UPPER BOUND(ID) transformation)


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

(22) Obligation:

Complexity RNTS consisting of the following rules:

duplicate(z) -{ 1 }→ 0 :|: z = 0
duplicate(z) -{ 2 + xs }→ 1 + x + (1 + x + s) :|: s >= 0, s <= 2 * xs, z = 1 + x + xs, xs >= 0, x >= 0
goal(z) -{ 2 + z }→ s' :|: s' >= 0, s' <= 2 * z, z >= 0

Function symbols to be analyzed: {goal}
Previous analysis results are:
duplicate: runtime: O(n1) [1 + z], size: O(n1) [2·z]
goal: runtime: ?, size: O(n1) [2·z]

(23) IntTrsBoundProof (UPPER BOUND(ID) transformation)


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

(24) Obligation:

Complexity RNTS consisting of the following rules:

duplicate(z) -{ 1 }→ 0 :|: z = 0
duplicate(z) -{ 2 + xs }→ 1 + x + (1 + x + s) :|: s >= 0, s <= 2 * xs, z = 1 + x + xs, xs >= 0, x >= 0
goal(z) -{ 2 + z }→ s' :|: s' >= 0, s' <= 2 * z, z >= 0

Function symbols to be analyzed:
Previous analysis results are:
duplicate: runtime: O(n1) [1 + z], size: O(n1) [2·z]
goal: runtime: O(n1) [2 + z], size: O(n1) [2·z]

(25) FinalProof (EQUIVALENT transformation)

Computed overall runtime complexity

(26) BOUNDS(1, n^1)