/export/starexec/sandbox/solver/bin/starexec_run_complexity /export/starexec/sandbox/benchmark/theBenchmark.xml /export/starexec/sandbox/output/output_files -------------------------------------------------------------------------------- WORST_CASE(Omega(n^3), O(n^3)) proof of /export/starexec/sandbox/benchmark/theBenchmark.xml # AProVE Commit ID: 794c25de1cacf0d048858bcd21c9a779e1221865 marcel 20200619 unpublished dirty The Runtime Complexity (innermost) of the given CpxTRS could be proven to be BOUNDS(n^3, n^3). (0) CpxTRS (1) RelTrsToWeightedTrsProof [BOTH BOUNDS(ID, ID), 0 ms] (2) CpxWeightedTrs (3) TypeInferenceProof [BOTH BOUNDS(ID, ID), 0 ms] (4) CpxTypedWeightedTrs (5) CompletionProof [UPPER BOUND(ID), 4 ms] (6) CpxTypedWeightedCompleteTrs (7) CpxTypedWeightedTrsToRntsProof [UPPER BOUND(ID), 0 ms] (8) CpxRNTS (9) CompleteCoflocoProof [FINISHED, 208 ms] (10) BOUNDS(1, n^3) (11) RenamingProof [BOTH BOUNDS(ID, ID), 0 ms] (12) CpxTRS (13) SlicingProof [LOWER BOUND(ID), 0 ms] (14) CpxTRS (15) TypeInferenceProof [BOTH BOUNDS(ID, ID), 0 ms] (16) typed CpxTrs (17) OrderProof [LOWER BOUND(ID), 0 ms] (18) typed CpxTrs (19) RewriteLemmaProof [LOWER BOUND(ID), 278 ms] (20) BEST (21) proven lower bound (22) LowerBoundPropagationProof [FINISHED, 0 ms] (23) BOUNDS(n^1, INF) (24) typed CpxTrs (25) RewriteLemmaProof [LOWER BOUND(ID), 16 ms] (26) BEST (27) proven lower bound (28) LowerBoundPropagationProof [FINISHED, 0 ms] (29) BOUNDS(n^2, INF) (30) typed CpxTrs (31) RewriteLemmaProof [LOWER BOUND(ID), 0 ms] (32) proven lower bound (33) LowerBoundPropagationProof [FINISHED, 0 ms] (34) BOUNDS(n^3, INF) ---------------------------------------- (0) Obligation: The Runtime Complexity (innermost) of the given CpxTRS could be proven to be BOUNDS(n^3, n^3). The TRS R consists of the following rules: shuffle(Cons(x, xs)) -> Cons(x, shuffle(reverse(xs))) reverse(Cons(x, xs)) -> append(reverse(xs), Cons(x, Nil)) append(Cons(x, xs), ys) -> Cons(x, append(xs, ys)) shuffle(Nil) -> Nil reverse(Nil) -> Nil append(Nil, ys) -> ys goal(xs) -> shuffle(xs) S is empty. Rewrite Strategy: INNERMOST ---------------------------------------- (1) RelTrsToWeightedTrsProof (BOTH BOUNDS(ID, ID)) Transformed relative TRS to weighted TRS ---------------------------------------- (2) Obligation: The Runtime Complexity (innermost) of the given CpxWeightedTrs could be proven to be BOUNDS(1, n^3). The TRS R consists of the following rules: shuffle(Cons(x, xs)) -> Cons(x, shuffle(reverse(xs))) [1] reverse(Cons(x, xs)) -> append(reverse(xs), Cons(x, Nil)) [1] append(Cons(x, xs), ys) -> Cons(x, append(xs, ys)) [1] shuffle(Nil) -> Nil [1] reverse(Nil) -> Nil [1] append(Nil, ys) -> ys [1] goal(xs) -> shuffle(xs) [1] Rewrite Strategy: INNERMOST ---------------------------------------- (3) TypeInferenceProof (BOTH BOUNDS(ID, ID)) Infered types. ---------------------------------------- (4) Obligation: Runtime Complexity Weighted TRS with Types. The TRS R consists of the following rules: shuffle(Cons(x, xs)) -> Cons(x, shuffle(reverse(xs))) [1] reverse(Cons(x, xs)) -> append(reverse(xs), Cons(x, Nil)) [1] append(Cons(x, xs), ys) -> Cons(x, append(xs, ys)) [1] shuffle(Nil) -> Nil [1] reverse(Nil) -> Nil [1] append(Nil, ys) -> ys [1] goal(xs) -> shuffle(xs) [1] The TRS has the following type information: shuffle :: Cons:Nil -> Cons:Nil Cons :: a -> Cons:Nil -> Cons:Nil reverse :: Cons:Nil -> Cons:Nil append :: Cons:Nil -> Cons:Nil -> Cons:Nil Nil :: Cons:Nil goal :: Cons:Nil -> Cons:Nil Rewrite Strategy: INNERMOST ---------------------------------------- (5) CompletionProof (UPPER BOUND(ID)) The TRS is a completely defined constructor system, as every type has a constant constructor and the following rules were added: none And the following fresh constants: const ---------------------------------------- (6) Obligation: Runtime Complexity Weighted TRS where all functions are completely defined. The underlying TRS is: Runtime Complexity Weighted TRS with Types. The TRS R consists of the following rules: shuffle(Cons(x, xs)) -> Cons(x, shuffle(reverse(xs))) [1] reverse(Cons(x, xs)) -> append(reverse(xs), Cons(x, Nil)) [1] append(Cons(x, xs), ys) -> Cons(x, append(xs, ys)) [1] shuffle(Nil) -> Nil [1] reverse(Nil) -> Nil [1] append(Nil, ys) -> ys [1] goal(xs) -> shuffle(xs) [1] The TRS has the following type information: shuffle :: Cons:Nil -> Cons:Nil Cons :: a -> Cons:Nil -> Cons:Nil reverse :: Cons:Nil -> Cons:Nil append :: Cons:Nil -> Cons:Nil -> Cons:Nil Nil :: Cons:Nil goal :: Cons:Nil -> Cons:Nil const :: a Rewrite Strategy: INNERMOST ---------------------------------------- (7) CpxTypedWeightedTrsToRntsProof (UPPER BOUND(ID)) Transformed the TRS into an over-approximating RNTS by (improved) Size Abstraction. The constant constructors are abstracted as follows: Nil => 0 const => 0 ---------------------------------------- (8) Obligation: Complexity RNTS consisting of the following rules: append(z, z') -{ 1 }-> ys :|: z' = ys, ys >= 0, z = 0 append(z, z') -{ 1 }-> 1 + x + append(xs, ys) :|: z = 1 + x + xs, xs >= 0, z' = ys, ys >= 0, x >= 0 goal(z) -{ 1 }-> shuffle(xs) :|: xs >= 0, z = xs reverse(z) -{ 1 }-> append(reverse(xs), 1 + x + 0) :|: z = 1 + x + xs, xs >= 0, x >= 0 reverse(z) -{ 1 }-> 0 :|: z = 0 shuffle(z) -{ 1 }-> 0 :|: z = 0 shuffle(z) -{ 1 }-> 1 + x + shuffle(reverse(xs)) :|: z = 1 + x + xs, xs >= 0, x >= 0 Only complete derivations are relevant for the runtime complexity. ---------------------------------------- (9) CompleteCoflocoProof (FINISHED) Transformed the RNTS (where only complete derivations are relevant) into cost relations for CoFloCo: eq(start(V, V5),0,[shuffle(V, Out)],[V >= 0]). eq(start(V, V5),0,[reverse(V, Out)],[V >= 0]). eq(start(V, V5),0,[append(V, V5, Out)],[V >= 0,V5 >= 0]). eq(start(V, V5),0,[goal(V, Out)],[V >= 0]). eq(shuffle(V, Out),1,[reverse(V1, Ret10),shuffle(Ret10, Ret1)],[Out = 1 + Ret1 + V2,V = 1 + V1 + V2,V1 >= 0,V2 >= 0]). eq(reverse(V, Out),1,[reverse(V4, Ret0),append(Ret0, 1 + V3 + 0, Ret)],[Out = Ret,V = 1 + V3 + V4,V4 >= 0,V3 >= 0]). eq(append(V, V5, Out),1,[append(V8, V7, Ret11)],[Out = 1 + Ret11 + V6,V = 1 + V6 + V8,V8 >= 0,V5 = V7,V7 >= 0,V6 >= 0]). eq(shuffle(V, Out),1,[],[Out = 0,V = 0]). eq(reverse(V, Out),1,[],[Out = 0,V = 0]). eq(append(V, V5, Out),1,[],[Out = V9,V5 = V9,V9 >= 0,V = 0]). eq(goal(V, Out),1,[shuffle(V10, Ret2)],[Out = Ret2,V10 >= 0,V = V10]). input_output_vars(shuffle(V,Out),[V],[Out]). input_output_vars(reverse(V,Out),[V],[Out]). input_output_vars(append(V,V5,Out),[V,V5],[Out]). input_output_vars(goal(V,Out),[V],[Out]). CoFloCo proof output: Preprocessing Cost Relations ===================================== #### Computed strongly connected components 0. recursive : [append/3] 1. recursive [non_tail] : [reverse/2] 2. recursive : [shuffle/2] 3. non_recursive : [goal/2] 4. non_recursive : [start/2] #### Obtained direct recursion through partial evaluation 0. SCC is partially evaluated into append/3 1. SCC is partially evaluated into reverse/2 2. SCC is partially evaluated into shuffle/2 3. SCC is completely evaluated into other SCCs 4. SCC is partially evaluated into start/2 Control-Flow Refinement of Cost Relations ===================================== ### Specialization of cost equations append/3 * CE 10 is refined into CE [11] * CE 9 is refined into CE [12] ### Cost equations --> "Loop" of append/3 * CEs [12] --> Loop 8 * CEs [11] --> Loop 9 ### Ranking functions of CR append(V,V5,Out) * RF of phase [8]: [V] #### Partial ranking functions of CR append(V,V5,Out) * Partial RF of phase [8]: - RF of loop [8:1]: V ### Specialization of cost equations reverse/2 * CE 8 is refined into CE [13] * CE 7 is refined into CE [14,15] ### Cost equations --> "Loop" of reverse/2 * CEs [15] --> Loop 10 * CEs [14] --> Loop 11 * CEs [13] --> Loop 12 ### Ranking functions of CR reverse(V,Out) * RF of phase [10]: [V] #### Partial ranking functions of CR reverse(V,Out) * Partial RF of phase [10]: - RF of loop [10:1]: V ### Specialization of cost equations shuffle/2 * CE 6 is refined into CE [16] * CE 5 is refined into CE [17,18] ### Cost equations --> "Loop" of shuffle/2 * CEs [18] --> Loop 13 * CEs [17] --> Loop 14 * CEs [16] --> Loop 15 ### Ranking functions of CR shuffle(V,Out) * RF of phase [13]: [V-1] #### Partial ranking functions of CR shuffle(V,Out) * Partial RF of phase [13]: - RF of loop [13:1]: V-1 ### Specialization of cost equations start/2 * CE 1 is refined into CE [19,20] * CE 2 is refined into CE [21,22] * CE 3 is refined into CE [23,24] * CE 4 is refined into CE [25,26] ### Cost equations --> "Loop" of start/2 * CEs [20,22,24,26] --> Loop 16 * CEs [19,21,23,25] --> Loop 17 ### Ranking functions of CR start(V,V5) #### Partial ranking functions of CR start(V,V5) Computing Bounds ===================================== #### Cost of chains of append(V,V5,Out): * Chain [[8],9]: 1*it(8)+1 Such that:it(8) =< -V5+Out with precondition: [V+V5=Out,V>=1,V5>=0] * Chain [9]: 1 with precondition: [V=0,V5=Out,V5>=0] #### Cost of chains of reverse(V,Out): * Chain [[10],11,12]: 2*it(10)+1*s(3)+3 Such that:aux(3) =< Out it(10) =< aux(3) s(3) =< it(10)*aux(3) with precondition: [Out=V,Out>=2] * Chain [12]: 1 with precondition: [V=0,Out=0] * Chain [11,12]: 3 with precondition: [V=Out,V>=1] #### Cost of chains of shuffle(V,Out): * Chain [[13],14,15]: 4*it(13)+2*s(13)+1*s(14)+3 Such that:aux(6) =< Out it(13) =< aux(6) aux(4) =< aux(6) s(15) =< it(13)*aux(4) s(13) =< s(15) s(14) =< s(13)*aux(6) with precondition: [V=Out,V>=2] * Chain [15]: 1 with precondition: [V=0,Out=0] * Chain [14,15]: 3 with precondition: [V=Out,V>=1] #### Cost of chains of start(V,V5): * Chain [17]: 2 with precondition: [V=0] * Chain [16]: 11*s(23)+4*s(26)+2*s(27)+1*s(30)+4 Such that:aux(7) =< V s(23) =< aux(7) s(24) =< aux(7) s(25) =< s(23)*s(24) s(26) =< s(25) s(27) =< s(26)*aux(7) s(30) =< s(23)*aux(7) with precondition: [V>=1] Closed-form bounds of start(V,V5): ------------------------------------- * Chain [17] with precondition: [V=0] - Upper bound: 2 - Complexity: constant * Chain [16] with precondition: [V>=1] - Upper bound: 11*V+4+5*V*V+2*V*V*V - Complexity: n^3 ### Maximum cost of start(V,V5): 11*V+2+5*V*V+2*V*V*V+2 Asymptotic class: n^3 * Total analysis performed in 133 ms. ---------------------------------------- (10) BOUNDS(1, n^3) ---------------------------------------- (11) RenamingProof (BOTH BOUNDS(ID, ID)) Renamed function symbols to avoid clashes with predefined symbol. ---------------------------------------- (12) Obligation: The Runtime Complexity (innermost) of the given CpxTRS could be proven to be BOUNDS(n^3, INF). The TRS R consists of the following rules: shuffle(Cons(x, xs)) -> Cons(x, shuffle(reverse(xs))) reverse(Cons(x, xs)) -> append(reverse(xs), Cons(x, Nil)) append(Cons(x, xs), ys) -> Cons(x, append(xs, ys)) shuffle(Nil) -> Nil reverse(Nil) -> Nil append(Nil, ys) -> ys goal(xs) -> shuffle(xs) S is empty. Rewrite Strategy: INNERMOST ---------------------------------------- (13) SlicingProof (LOWER BOUND(ID)) Sliced the following arguments: Cons/0 ---------------------------------------- (14) Obligation: The Runtime Complexity (innermost) of the given CpxTRS could be proven to be BOUNDS(n^3, INF). The TRS R consists of the following rules: shuffle(Cons(xs)) -> Cons(shuffle(reverse(xs))) reverse(Cons(xs)) -> append(reverse(xs), Cons(Nil)) append(Cons(xs), ys) -> Cons(append(xs, ys)) shuffle(Nil) -> Nil reverse(Nil) -> Nil append(Nil, ys) -> ys goal(xs) -> shuffle(xs) S is empty. Rewrite Strategy: INNERMOST ---------------------------------------- (15) TypeInferenceProof (BOTH BOUNDS(ID, ID)) Infered types. ---------------------------------------- (16) Obligation: Innermost TRS: Rules: shuffle(Cons(xs)) -> Cons(shuffle(reverse(xs))) reverse(Cons(xs)) -> append(reverse(xs), Cons(Nil)) append(Cons(xs), ys) -> Cons(append(xs, ys)) shuffle(Nil) -> Nil reverse(Nil) -> Nil append(Nil, ys) -> ys goal(xs) -> shuffle(xs) Types: shuffle :: Cons:Nil -> Cons:Nil Cons :: Cons:Nil -> Cons:Nil reverse :: Cons:Nil -> Cons:Nil append :: Cons:Nil -> Cons:Nil -> Cons:Nil Nil :: Cons:Nil goal :: Cons:Nil -> Cons:Nil hole_Cons:Nil1_0 :: Cons:Nil gen_Cons:Nil2_0 :: Nat -> Cons:Nil ---------------------------------------- (17) OrderProof (LOWER BOUND(ID)) Heuristically decided to analyse the following defined symbols: shuffle, reverse, append They will be analysed ascendingly in the following order: reverse < shuffle append < reverse ---------------------------------------- (18) Obligation: Innermost TRS: Rules: shuffle(Cons(xs)) -> Cons(shuffle(reverse(xs))) reverse(Cons(xs)) -> append(reverse(xs), Cons(Nil)) append(Cons(xs), ys) -> Cons(append(xs, ys)) shuffle(Nil) -> Nil reverse(Nil) -> Nil append(Nil, ys) -> ys goal(xs) -> shuffle(xs) Types: shuffle :: Cons:Nil -> Cons:Nil Cons :: Cons:Nil -> Cons:Nil reverse :: Cons:Nil -> Cons:Nil append :: Cons:Nil -> Cons:Nil -> Cons:Nil Nil :: Cons:Nil goal :: Cons:Nil -> Cons:Nil hole_Cons:Nil1_0 :: Cons:Nil gen_Cons:Nil2_0 :: Nat -> Cons:Nil Generator Equations: gen_Cons:Nil2_0(0) <=> Nil gen_Cons:Nil2_0(+(x, 1)) <=> Cons(gen_Cons:Nil2_0(x)) The following defined symbols remain to be analysed: append, shuffle, reverse They will be analysed ascendingly in the following order: reverse < shuffle append < reverse ---------------------------------------- (19) RewriteLemmaProof (LOWER BOUND(ID)) Proved the following rewrite lemma: append(gen_Cons:Nil2_0(n4_0), gen_Cons:Nil2_0(b)) -> gen_Cons:Nil2_0(+(n4_0, b)), rt in Omega(1 + n4_0) Induction Base: append(gen_Cons:Nil2_0(0), gen_Cons:Nil2_0(b)) ->_R^Omega(1) gen_Cons:Nil2_0(b) Induction Step: append(gen_Cons:Nil2_0(+(n4_0, 1)), gen_Cons:Nil2_0(b)) ->_R^Omega(1) Cons(append(gen_Cons:Nil2_0(n4_0), gen_Cons:Nil2_0(b))) ->_IH Cons(gen_Cons:Nil2_0(+(b, c5_0))) We have rt in Omega(n^1) and sz in O(n). Thus, we have irc_R in Omega(n). ---------------------------------------- (20) Complex Obligation (BEST) ---------------------------------------- (21) Obligation: Proved the lower bound n^1 for the following obligation: Innermost TRS: Rules: shuffle(Cons(xs)) -> Cons(shuffle(reverse(xs))) reverse(Cons(xs)) -> append(reverse(xs), Cons(Nil)) append(Cons(xs), ys) -> Cons(append(xs, ys)) shuffle(Nil) -> Nil reverse(Nil) -> Nil append(Nil, ys) -> ys goal(xs) -> shuffle(xs) Types: shuffle :: Cons:Nil -> Cons:Nil Cons :: Cons:Nil -> Cons:Nil reverse :: Cons:Nil -> Cons:Nil append :: Cons:Nil -> Cons:Nil -> Cons:Nil Nil :: Cons:Nil goal :: Cons:Nil -> Cons:Nil hole_Cons:Nil1_0 :: Cons:Nil gen_Cons:Nil2_0 :: Nat -> Cons:Nil Generator Equations: gen_Cons:Nil2_0(0) <=> Nil gen_Cons:Nil2_0(+(x, 1)) <=> Cons(gen_Cons:Nil2_0(x)) The following defined symbols remain to be analysed: append, shuffle, reverse They will be analysed ascendingly in the following order: reverse < shuffle append < reverse ---------------------------------------- (22) LowerBoundPropagationProof (FINISHED) Propagated lower bound. ---------------------------------------- (23) BOUNDS(n^1, INF) ---------------------------------------- (24) Obligation: Innermost TRS: Rules: shuffle(Cons(xs)) -> Cons(shuffle(reverse(xs))) reverse(Cons(xs)) -> append(reverse(xs), Cons(Nil)) append(Cons(xs), ys) -> Cons(append(xs, ys)) shuffle(Nil) -> Nil reverse(Nil) -> Nil append(Nil, ys) -> ys goal(xs) -> shuffle(xs) Types: shuffle :: Cons:Nil -> Cons:Nil Cons :: Cons:Nil -> Cons:Nil reverse :: Cons:Nil -> Cons:Nil append :: Cons:Nil -> Cons:Nil -> Cons:Nil Nil :: Cons:Nil goal :: Cons:Nil -> Cons:Nil hole_Cons:Nil1_0 :: Cons:Nil gen_Cons:Nil2_0 :: Nat -> Cons:Nil Lemmas: append(gen_Cons:Nil2_0(n4_0), gen_Cons:Nil2_0(b)) -> gen_Cons:Nil2_0(+(n4_0, b)), rt in Omega(1 + n4_0) Generator Equations: gen_Cons:Nil2_0(0) <=> Nil gen_Cons:Nil2_0(+(x, 1)) <=> Cons(gen_Cons:Nil2_0(x)) The following defined symbols remain to be analysed: reverse, shuffle They will be analysed ascendingly in the following order: reverse < shuffle ---------------------------------------- (25) RewriteLemmaProof (LOWER BOUND(ID)) Proved the following rewrite lemma: reverse(gen_Cons:Nil2_0(n504_0)) -> gen_Cons:Nil2_0(n504_0), rt in Omega(1 + n504_0 + n504_0^2) Induction Base: reverse(gen_Cons:Nil2_0(0)) ->_R^Omega(1) Nil Induction Step: reverse(gen_Cons:Nil2_0(+(n504_0, 1))) ->_R^Omega(1) append(reverse(gen_Cons:Nil2_0(n504_0)), Cons(Nil)) ->_IH append(gen_Cons:Nil2_0(c505_0), Cons(Nil)) ->_L^Omega(1 + n504_0) gen_Cons:Nil2_0(+(n504_0, +(0, 1))) We have rt in Omega(n^2) and sz in O(n). Thus, we have irc_R in Omega(n^2). ---------------------------------------- (26) Complex Obligation (BEST) ---------------------------------------- (27) Obligation: Proved the lower bound n^2 for the following obligation: Innermost TRS: Rules: shuffle(Cons(xs)) -> Cons(shuffle(reverse(xs))) reverse(Cons(xs)) -> append(reverse(xs), Cons(Nil)) append(Cons(xs), ys) -> Cons(append(xs, ys)) shuffle(Nil) -> Nil reverse(Nil) -> Nil append(Nil, ys) -> ys goal(xs) -> shuffle(xs) Types: shuffle :: Cons:Nil -> Cons:Nil Cons :: Cons:Nil -> Cons:Nil reverse :: Cons:Nil -> Cons:Nil append :: Cons:Nil -> Cons:Nil -> Cons:Nil Nil :: Cons:Nil goal :: Cons:Nil -> Cons:Nil hole_Cons:Nil1_0 :: Cons:Nil gen_Cons:Nil2_0 :: Nat -> Cons:Nil Lemmas: append(gen_Cons:Nil2_0(n4_0), gen_Cons:Nil2_0(b)) -> gen_Cons:Nil2_0(+(n4_0, b)), rt in Omega(1 + n4_0) Generator Equations: gen_Cons:Nil2_0(0) <=> Nil gen_Cons:Nil2_0(+(x, 1)) <=> Cons(gen_Cons:Nil2_0(x)) The following defined symbols remain to be analysed: reverse, shuffle They will be analysed ascendingly in the following order: reverse < shuffle ---------------------------------------- (28) LowerBoundPropagationProof (FINISHED) Propagated lower bound. ---------------------------------------- (29) BOUNDS(n^2, INF) ---------------------------------------- (30) Obligation: Innermost TRS: Rules: shuffle(Cons(xs)) -> Cons(shuffle(reverse(xs))) reverse(Cons(xs)) -> append(reverse(xs), Cons(Nil)) append(Cons(xs), ys) -> Cons(append(xs, ys)) shuffle(Nil) -> Nil reverse(Nil) -> Nil append(Nil, ys) -> ys goal(xs) -> shuffle(xs) Types: shuffle :: Cons:Nil -> Cons:Nil Cons :: Cons:Nil -> Cons:Nil reverse :: Cons:Nil -> Cons:Nil append :: Cons:Nil -> Cons:Nil -> Cons:Nil Nil :: Cons:Nil goal :: Cons:Nil -> Cons:Nil hole_Cons:Nil1_0 :: Cons:Nil gen_Cons:Nil2_0 :: Nat -> Cons:Nil Lemmas: append(gen_Cons:Nil2_0(n4_0), gen_Cons:Nil2_0(b)) -> gen_Cons:Nil2_0(+(n4_0, b)), rt in Omega(1 + n4_0) reverse(gen_Cons:Nil2_0(n504_0)) -> gen_Cons:Nil2_0(n504_0), rt in Omega(1 + n504_0 + n504_0^2) Generator Equations: gen_Cons:Nil2_0(0) <=> Nil gen_Cons:Nil2_0(+(x, 1)) <=> Cons(gen_Cons:Nil2_0(x)) The following defined symbols remain to be analysed: shuffle ---------------------------------------- (31) RewriteLemmaProof (LOWER BOUND(ID)) Proved the following rewrite lemma: shuffle(gen_Cons:Nil2_0(n719_0)) -> gen_Cons:Nil2_0(n719_0), rt in Omega(1 + n719_0 + n719_0^2 + n719_0^3) Induction Base: shuffle(gen_Cons:Nil2_0(0)) ->_R^Omega(1) Nil Induction Step: shuffle(gen_Cons:Nil2_0(+(n719_0, 1))) ->_R^Omega(1) Cons(shuffle(reverse(gen_Cons:Nil2_0(n719_0)))) ->_L^Omega(1 + n719_0 + n719_0^2) Cons(shuffle(gen_Cons:Nil2_0(n719_0))) ->_IH Cons(gen_Cons:Nil2_0(c720_0)) We have rt in Omega(n^3) and sz in O(n). Thus, we have irc_R in Omega(n^3). ---------------------------------------- (32) Obligation: Proved the lower bound n^3 for the following obligation: Innermost TRS: Rules: shuffle(Cons(xs)) -> Cons(shuffle(reverse(xs))) reverse(Cons(xs)) -> append(reverse(xs), Cons(Nil)) append(Cons(xs), ys) -> Cons(append(xs, ys)) shuffle(Nil) -> Nil reverse(Nil) -> Nil append(Nil, ys) -> ys goal(xs) -> shuffle(xs) Types: shuffle :: Cons:Nil -> Cons:Nil Cons :: Cons:Nil -> Cons:Nil reverse :: Cons:Nil -> Cons:Nil append :: Cons:Nil -> Cons:Nil -> Cons:Nil Nil :: Cons:Nil goal :: Cons:Nil -> Cons:Nil hole_Cons:Nil1_0 :: Cons:Nil gen_Cons:Nil2_0 :: Nat -> Cons:Nil Lemmas: append(gen_Cons:Nil2_0(n4_0), gen_Cons:Nil2_0(b)) -> gen_Cons:Nil2_0(+(n4_0, b)), rt in Omega(1 + n4_0) reverse(gen_Cons:Nil2_0(n504_0)) -> gen_Cons:Nil2_0(n504_0), rt in Omega(1 + n504_0 + n504_0^2) Generator Equations: gen_Cons:Nil2_0(0) <=> Nil gen_Cons:Nil2_0(+(x, 1)) <=> Cons(gen_Cons:Nil2_0(x)) The following defined symbols remain to be analysed: shuffle ---------------------------------------- (33) LowerBoundPropagationProof (FINISHED) Propagated lower bound. ---------------------------------------- (34) BOUNDS(n^3, INF)