(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:

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

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:

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

Rewrite Strategy: INNERMOST

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

Renamed defined symbols to avoid conflicts with arithmetic symbols:

+ => plus

(4) 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:

plus(0, y) → y [1]
plus(s(x), 0) → s(x) [1]
plus(s(x), s(y)) → s(plus(s(x), plus(y, 0))) [1]

Rewrite Strategy: INNERMOST

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

Infered types.

(6) Obligation:

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

plus(0, y) → y [1]
plus(s(x), 0) → s(x) [1]
plus(s(x), s(y)) → s(plus(s(x), plus(y, 0))) [1]

The TRS has the following type information:
plus :: 0:s → 0:s → 0:s
0 :: 0:s
s :: 0:s → 0:s

Rewrite Strategy: INNERMOST

(7) 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:
none

(c) The following functions are completely defined:


plus

Due to the following rules being added:
none

And the following fresh constants: none

(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:

plus(0, y) → y [1]
plus(s(x), 0) → s(x) [1]
plus(s(x), s(y)) → s(plus(s(x), plus(y, 0))) [1]

The TRS has the following type information:
plus :: 0:s → 0:s → 0:s
0 :: 0:s
s :: 0:s → 0:s

Rewrite Strategy: INNERMOST

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

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

(10) 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:

plus(0, y) → y [1]
plus(s(x), 0) → s(x) [1]
plus(s(x), s(0)) → s(plus(s(x), 0)) [2]
plus(s(x), s(s(x'))) → s(plus(s(x), s(x'))) [2]

The TRS has the following type information:
plus :: 0:s → 0:s → 0:s
0 :: 0:s
s :: 0:s → 0:s

Rewrite Strategy: INNERMOST

(11) 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

(12) Obligation:

Complexity RNTS consisting of the following rules:

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

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

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

(14) Obligation:

Complexity RNTS consisting of the following rules:

plus(z, z') -{ 1 }→ z' :|: z' >= 0, z = 0
plus(z, z') -{ 2 }→ 1 + plus(1 + (z - 1), 0) :|: z - 1 >= 0, z' = 1 + 0
plus(z, z') -{ 2 }→ 1 + plus(1 + (z - 1), 1 + (z' - 2)) :|: z - 1 >= 0, z' - 2 >= 0
plus(z, z') -{ 1 }→ 1 + (z - 1) :|: z - 1 >= 0, z' = 0

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

Found the following analysis order by SCC decomposition:

{ plus }

(16) Obligation:

Complexity RNTS consisting of the following rules:

plus(z, z') -{ 1 }→ z' :|: z' >= 0, z = 0
plus(z, z') -{ 2 }→ 1 + plus(1 + (z - 1), 0) :|: z - 1 >= 0, z' = 1 + 0
plus(z, z') -{ 2 }→ 1 + plus(1 + (z - 1), 1 + (z' - 2)) :|: z - 1 >= 0, z' - 2 >= 0
plus(z, z') -{ 1 }→ 1 + (z - 1) :|: z - 1 >= 0, z' = 0

Function symbols to be analyzed: {plus}

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


Computed SIZE bound using KoAT for: plus
after applying outer abstraction to obtain an ITS,
resulting in: O(n1) with polynomial bound: z + z'

(18) Obligation:

Complexity RNTS consisting of the following rules:

plus(z, z') -{ 1 }→ z' :|: z' >= 0, z = 0
plus(z, z') -{ 2 }→ 1 + plus(1 + (z - 1), 0) :|: z - 1 >= 0, z' = 1 + 0
plus(z, z') -{ 2 }→ 1 + plus(1 + (z - 1), 1 + (z' - 2)) :|: z - 1 >= 0, z' - 2 >= 0
plus(z, z') -{ 1 }→ 1 + (z - 1) :|: z - 1 >= 0, z' = 0

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

(19) IntTrsBoundProof (UPPER BOUND(ID) transformation)


Computed RUNTIME bound using PUBS for: plus
after applying outer abstraction to obtain an ITS,
resulting in: O(n1) with polynomial bound: 1 + 2·z'

(20) Obligation:

Complexity RNTS consisting of the following rules:

plus(z, z') -{ 1 }→ z' :|: z' >= 0, z = 0
plus(z, z') -{ 2 }→ 1 + plus(1 + (z - 1), 0) :|: z - 1 >= 0, z' = 1 + 0
plus(z, z') -{ 2 }→ 1 + plus(1 + (z - 1), 1 + (z' - 2)) :|: z - 1 >= 0, z' - 2 >= 0
plus(z, z') -{ 1 }→ 1 + (z - 1) :|: z - 1 >= 0, z' = 0

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

(21) FinalProof (EQUIVALENT transformation)

Computed overall runtime complexity

(22) BOUNDS(1, n^1)