NO proof of /export/starexec/sandbox2/benchmark/theBenchmark.xml # AProVE Commit ID: 794c25de1cacf0d048858bcd21c9a779e1221865 marcel 20200619 unpublished dirty Termination w.r.t. Q of the given QTRS could be disproven: (0) QTRS (1) QTRSRRRProof [EQUIVALENT, 52 ms] (2) QTRS (3) AAECC Innermost [EQUIVALENT, 0 ms] (4) QTRS (5) DependencyPairsProof [EQUIVALENT, 0 ms] (6) QDP (7) DependencyGraphProof [EQUIVALENT, 0 ms] (8) QDP (9) UsableRulesProof [EQUIVALENT, 0 ms] (10) QDP (11) QReductionProof [EQUIVALENT, 0 ms] (12) QDP (13) TransformationProof [EQUIVALENT, 0 ms] (14) QDP (15) TransformationProof [EQUIVALENT, 0 ms] (16) QDP (17) UsableRulesProof [EQUIVALENT, 0 ms] (18) QDP (19) QReductionProof [EQUIVALENT, 0 ms] (20) QDP (21) TransformationProof [EQUIVALENT, 0 ms] (22) QDP (23) TransformationProof [EQUIVALENT, 0 ms] (24) QDP (25) TransformationProof [EQUIVALENT, 0 ms] (26) QDP (27) TransformationProof [EQUIVALENT, 0 ms] (28) QDP (29) NonTerminationLoopProof [COMPLETE, 0 ms] (30) NO ---------------------------------------- (0) Obligation: Q restricted rewrite system: The TRS R consists of the following rules: f(x, x) -> f(i(x), g(g(x))) f(x, y) -> x g(x) -> i(x) f(x, i(x)) -> f(x, x) f(i(x), i(g(x))) -> a Q is empty. ---------------------------------------- (1) QTRSRRRProof (EQUIVALENT) Used ordering: Polynomial interpretation [POLO]: POL(a) = 0 POL(f(x_1, x_2)) = 1 + 2*x_1 + 2*x_2 POL(g(x_1)) = x_1 POL(i(x_1)) = x_1 With this ordering the following rules can be removed by the rule removal processor [LPAR04] because they are oriented strictly: f(x, y) -> x f(i(x), i(g(x))) -> a ---------------------------------------- (2) Obligation: Q restricted rewrite system: The TRS R consists of the following rules: f(x, x) -> f(i(x), g(g(x))) g(x) -> i(x) f(x, i(x)) -> f(x, x) Q is empty. ---------------------------------------- (3) AAECC Innermost (EQUIVALENT) We have applied [NOC,AAECCNOC] to switch to innermost. The TRS R 1 is g(x) -> i(x) The TRS R 2 is f(x, x) -> f(i(x), g(g(x))) f(x, i(x)) -> f(x, x) The signature Sigma is {f_2} ---------------------------------------- (4) Obligation: Q restricted rewrite system: The TRS R consists of the following rules: f(x, x) -> f(i(x), g(g(x))) g(x) -> i(x) f(x, i(x)) -> f(x, x) The set Q consists of the following terms: f(x0, x0) g(x0) f(x0, i(x0)) ---------------------------------------- (5) DependencyPairsProof (EQUIVALENT) Using Dependency Pairs [AG00,LPAR04] we result in the following initial DP problem. ---------------------------------------- (6) Obligation: Q DP problem: The TRS P consists of the following rules: F(x, x) -> F(i(x), g(g(x))) F(x, x) -> G(g(x)) F(x, x) -> G(x) F(x, i(x)) -> F(x, x) The TRS R consists of the following rules: f(x, x) -> f(i(x), g(g(x))) g(x) -> i(x) f(x, i(x)) -> f(x, x) The set Q consists of the following terms: f(x0, x0) g(x0) f(x0, i(x0)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (7) DependencyGraphProof (EQUIVALENT) The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 1 SCC with 2 less nodes. ---------------------------------------- (8) Obligation: Q DP problem: The TRS P consists of the following rules: F(x, i(x)) -> F(x, x) F(x, x) -> F(i(x), g(g(x))) The TRS R consists of the following rules: f(x, x) -> f(i(x), g(g(x))) g(x) -> i(x) f(x, i(x)) -> f(x, x) The set Q consists of the following terms: f(x0, x0) g(x0) f(x0, i(x0)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (9) UsableRulesProof (EQUIVALENT) As all Q-normal forms are R-normal forms we are in the innermost case. Hence, by the usable rules processor [LPAR04] we can delete all non-usable rules [FROCOS05] from R. ---------------------------------------- (10) Obligation: Q DP problem: The TRS P consists of the following rules: F(x, i(x)) -> F(x, x) F(x, x) -> F(i(x), g(g(x))) The TRS R consists of the following rules: g(x) -> i(x) The set Q consists of the following terms: f(x0, x0) g(x0) f(x0, i(x0)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (11) QReductionProof (EQUIVALENT) We deleted the following terms from Q as each root-symbol of these terms does neither occur in P nor in R.[THIEMANN]. f(x0, x0) f(x0, i(x0)) ---------------------------------------- (12) Obligation: Q DP problem: The TRS P consists of the following rules: F(x, i(x)) -> F(x, x) F(x, x) -> F(i(x), g(g(x))) The TRS R consists of the following rules: g(x) -> i(x) The set Q consists of the following terms: g(x0) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (13) TransformationProof (EQUIVALENT) By rewriting [LPAR04] the rule F(x, x) -> F(i(x), g(g(x))) at position [1] we obtained the following new rules [LPAR04]: (F(x, x) -> F(i(x), i(g(x))),F(x, x) -> F(i(x), i(g(x)))) ---------------------------------------- (14) Obligation: Q DP problem: The TRS P consists of the following rules: F(x, i(x)) -> F(x, x) F(x, x) -> F(i(x), i(g(x))) The TRS R consists of the following rules: g(x) -> i(x) The set Q consists of the following terms: g(x0) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (15) TransformationProof (EQUIVALENT) By rewriting [LPAR04] the rule F(x, x) -> F(i(x), i(g(x))) at position [1,0] we obtained the following new rules [LPAR04]: (F(x, x) -> F(i(x), i(i(x))),F(x, x) -> F(i(x), i(i(x)))) ---------------------------------------- (16) Obligation: Q DP problem: The TRS P consists of the following rules: F(x, i(x)) -> F(x, x) F(x, x) -> F(i(x), i(i(x))) The TRS R consists of the following rules: g(x) -> i(x) The set Q consists of the following terms: g(x0) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (17) UsableRulesProof (EQUIVALENT) As all Q-normal forms are R-normal forms we are in the innermost case. Hence, by the usable rules processor [LPAR04] we can delete all non-usable rules [FROCOS05] from R. ---------------------------------------- (18) Obligation: Q DP problem: The TRS P consists of the following rules: F(x, i(x)) -> F(x, x) F(x, x) -> F(i(x), i(i(x))) R is empty. The set Q consists of the following terms: g(x0) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (19) QReductionProof (EQUIVALENT) We deleted the following terms from Q as each root-symbol of these terms does neither occur in P nor in R.[THIEMANN]. g(x0) ---------------------------------------- (20) Obligation: Q DP problem: The TRS P consists of the following rules: F(x, i(x)) -> F(x, x) F(x, x) -> F(i(x), i(i(x))) R is empty. Q is empty. We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (21) TransformationProof (EQUIVALENT) By instantiating [LPAR04] the rule F(x, i(x)) -> F(x, x) we obtained the following new rules [LPAR04]: (F(i(z0), i(i(z0))) -> F(i(z0), i(z0)),F(i(z0), i(i(z0))) -> F(i(z0), i(z0))) ---------------------------------------- (22) Obligation: Q DP problem: The TRS P consists of the following rules: F(x, x) -> F(i(x), i(i(x))) F(i(z0), i(i(z0))) -> F(i(z0), i(z0)) R is empty. Q is empty. We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (23) TransformationProof (EQUIVALENT) By instantiating [LPAR04] the rule F(x, x) -> F(i(x), i(i(x))) we obtained the following new rules [LPAR04]: (F(i(z0), i(z0)) -> F(i(i(z0)), i(i(i(z0)))),F(i(z0), i(z0)) -> F(i(i(z0)), i(i(i(z0))))) ---------------------------------------- (24) Obligation: Q DP problem: The TRS P consists of the following rules: F(i(z0), i(i(z0))) -> F(i(z0), i(z0)) F(i(z0), i(z0)) -> F(i(i(z0)), i(i(i(z0)))) R is empty. Q is empty. We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (25) TransformationProof (EQUIVALENT) By instantiating [LPAR04] the rule F(i(z0), i(i(z0))) -> F(i(z0), i(z0)) we obtained the following new rules [LPAR04]: (F(i(i(z0)), i(i(i(z0)))) -> F(i(i(z0)), i(i(z0))),F(i(i(z0)), i(i(i(z0)))) -> F(i(i(z0)), i(i(z0)))) ---------------------------------------- (26) Obligation: Q DP problem: The TRS P consists of the following rules: F(i(z0), i(z0)) -> F(i(i(z0)), i(i(i(z0)))) F(i(i(z0)), i(i(i(z0)))) -> F(i(i(z0)), i(i(z0))) R is empty. Q is empty. We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (27) TransformationProof (EQUIVALENT) By instantiating [LPAR04] the rule F(i(z0), i(z0)) -> F(i(i(z0)), i(i(i(z0)))) we obtained the following new rules [LPAR04]: (F(i(i(z0)), i(i(z0))) -> F(i(i(i(z0))), i(i(i(i(z0))))),F(i(i(z0)), i(i(z0))) -> F(i(i(i(z0))), i(i(i(i(z0)))))) ---------------------------------------- (28) Obligation: Q DP problem: The TRS P consists of the following rules: F(i(i(z0)), i(i(i(z0)))) -> F(i(i(z0)), i(i(z0))) F(i(i(z0)), i(i(z0))) -> F(i(i(i(z0))), i(i(i(i(z0))))) R is empty. Q is empty. We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (29) NonTerminationLoopProof (COMPLETE) We used the non-termination processor [FROCOS05] to show that the DP problem is infinite. Found a loop by narrowing to the left: s = F(i(i(z0')), i(i(z0'))) evaluates to t =F(i(i(i(z0'))), i(i(i(z0')))) Thus s starts an infinite chain as s semiunifies with t with the following substitutions: * Matcher: [z0' / i(z0')] * Semiunifier: [ ] -------------------------------------------------------------------------------- Rewriting sequence F(i(i(z0')), i(i(z0'))) -> F(i(i(i(z0'))), i(i(i(i(z0'))))) with rule F(i(i(z0'')), i(i(z0''))) -> F(i(i(i(z0''))), i(i(i(i(z0''))))) at position [] and matcher [z0'' / z0'] F(i(i(i(z0'))), i(i(i(i(z0'))))) -> F(i(i(i(z0'))), i(i(i(z0')))) with rule F(i(i(z0)), i(i(i(z0)))) -> F(i(i(z0)), i(i(z0))) Now applying the matcher to the start term leads to a term which is equal to the last term in the rewriting sequence All these steps are and every following step will be a correct step w.r.t to Q. ---------------------------------------- (30) NO