YES proof of /export/starexec/sandbox/benchmark/theBenchmark.xml # AProVE Commit ID: 794c25de1cacf0d048858bcd21c9a779e1221865 marcel 20200619 unpublished dirty Termination w.r.t. Q of the given QTRS could be proven: (0) QTRS (1) QTRS Reverse [EQUIVALENT, 0 ms] (2) QTRS (3) QTRSRRRProof [EQUIVALENT, 14 ms] (4) QTRS (5) AAECC Innermost [EQUIVALENT, 0 ms] (6) QTRS (7) DependencyPairsProof [EQUIVALENT, 8 ms] (8) QDP (9) DependencyGraphProof [EQUIVALENT, 0 ms] (10) AND (11) QDP (12) UsableRulesProof [EQUIVALENT, 0 ms] (13) QDP (14) QReductionProof [EQUIVALENT, 2 ms] (15) QDP (16) QDPOrderProof [EQUIVALENT, 0 ms] (17) QDP (18) PisEmptyProof [EQUIVALENT, 0 ms] (19) YES (20) QDP (21) UsableRulesProof [EQUIVALENT, 0 ms] (22) QDP (23) QReductionProof [EQUIVALENT, 0 ms] (24) QDP (25) QDPSizeChangeProof [EQUIVALENT, 0 ms] (26) YES ---------------------------------------- (0) Obligation: Q restricted rewrite system: The TRS R consists of the following rules: f(0(x1)) -> s(0(x1)) d(0(x1)) -> 0(x1) d(s(x1)) -> s(s(d(p(s(x1))))) f(s(x1)) -> d(f(p(s(x1)))) p(s(x1)) -> x1 Q is empty. ---------------------------------------- (1) QTRS Reverse (EQUIVALENT) We applied the QTRS Reverse Processor [REVERSE]. ---------------------------------------- (2) Obligation: Q restricted rewrite system: The TRS R consists of the following rules: 0(f(x1)) -> 0(s(x1)) 0(d(x1)) -> 0(x1) s(d(x1)) -> s(p(d(s(s(x1))))) s(f(x1)) -> s(p(f(d(x1)))) s(p(x1)) -> x1 Q is empty. ---------------------------------------- (3) QTRSRRRProof (EQUIVALENT) Used ordering: Polynomial interpretation [POLO]: POL(0(x_1)) = x_1 POL(d(x_1)) = x_1 POL(f(x_1)) = 1 + x_1 POL(p(x_1)) = x_1 POL(s(x_1)) = x_1 With this ordering the following rules can be removed by the rule removal processor [LPAR04] because they are oriented strictly: 0(f(x1)) -> 0(s(x1)) ---------------------------------------- (4) Obligation: Q restricted rewrite system: The TRS R consists of the following rules: 0(d(x1)) -> 0(x1) s(d(x1)) -> s(p(d(s(s(x1))))) s(f(x1)) -> s(p(f(d(x1)))) s(p(x1)) -> x1 Q is empty. ---------------------------------------- (5) AAECC Innermost (EQUIVALENT) We have applied [NOC,AAECCNOC] to switch to innermost. The TRS R 1 is s(f(x1)) -> s(p(f(d(x1)))) s(p(x1)) -> x1 s(d(x1)) -> s(p(d(s(s(x1))))) The TRS R 2 is 0(d(x1)) -> 0(x1) The signature Sigma is {0_1} ---------------------------------------- (6) Obligation: Q restricted rewrite system: The TRS R consists of the following rules: 0(d(x1)) -> 0(x1) s(d(x1)) -> s(p(d(s(s(x1))))) s(f(x1)) -> s(p(f(d(x1)))) s(p(x1)) -> x1 The set Q consists of the following terms: 0(d(x0)) s(d(x0)) s(f(x0)) s(p(x0)) ---------------------------------------- (7) DependencyPairsProof (EQUIVALENT) Using Dependency Pairs [AG00,LPAR04] we result in the following initial DP problem. ---------------------------------------- (8) Obligation: Q DP problem: The TRS P consists of the following rules: 0^1(d(x1)) -> 0^1(x1) S(d(x1)) -> S(p(d(s(s(x1))))) S(d(x1)) -> S(s(x1)) S(d(x1)) -> S(x1) S(f(x1)) -> S(p(f(d(x1)))) The TRS R consists of the following rules: 0(d(x1)) -> 0(x1) s(d(x1)) -> s(p(d(s(s(x1))))) s(f(x1)) -> s(p(f(d(x1)))) s(p(x1)) -> x1 The set Q consists of the following terms: 0(d(x0)) s(d(x0)) s(f(x0)) s(p(x0)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (9) DependencyGraphProof (EQUIVALENT) The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 2 SCCs with 2 less nodes. ---------------------------------------- (10) Complex Obligation (AND) ---------------------------------------- (11) Obligation: Q DP problem: The TRS P consists of the following rules: S(d(x1)) -> S(x1) S(d(x1)) -> S(s(x1)) The TRS R consists of the following rules: 0(d(x1)) -> 0(x1) s(d(x1)) -> s(p(d(s(s(x1))))) s(f(x1)) -> s(p(f(d(x1)))) s(p(x1)) -> x1 The set Q consists of the following terms: 0(d(x0)) s(d(x0)) s(f(x0)) s(p(x0)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (12) 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. ---------------------------------------- (13) Obligation: Q DP problem: The TRS P consists of the following rules: S(d(x1)) -> S(x1) S(d(x1)) -> S(s(x1)) The TRS R consists of the following rules: s(d(x1)) -> s(p(d(s(s(x1))))) s(f(x1)) -> s(p(f(d(x1)))) s(p(x1)) -> x1 The set Q consists of the following terms: 0(d(x0)) s(d(x0)) s(f(x0)) s(p(x0)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (14) 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]. 0(d(x0)) ---------------------------------------- (15) Obligation: Q DP problem: The TRS P consists of the following rules: S(d(x1)) -> S(x1) S(d(x1)) -> S(s(x1)) The TRS R consists of the following rules: s(d(x1)) -> s(p(d(s(s(x1))))) s(f(x1)) -> s(p(f(d(x1)))) s(p(x1)) -> x1 The set Q consists of the following terms: s(d(x0)) s(f(x0)) s(p(x0)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (16) QDPOrderProof (EQUIVALENT) We use the reduction pair processor [LPAR04,JAR06]. The following pairs can be oriented strictly and are deleted. S(d(x1)) -> S(x1) S(d(x1)) -> S(s(x1)) The remaining pairs can at least be oriented weakly. Used ordering: Polynomial Order [NEGPOLO,POLO] with Interpretation: POL( S_1(x_1) ) = x_1 + 1 POL( s_1(x_1) ) = x_1 POL( d_1(x_1) ) = 2x_1 + 1 POL( p_1(x_1) ) = x_1 POL( f_1(x_1) ) = max{0, -2} The following usable rules [FROCOS05] with respect to the argument filtering of the ordering [JAR06] were oriented: s(d(x1)) -> s(p(d(s(s(x1))))) s(f(x1)) -> s(p(f(d(x1)))) s(p(x1)) -> x1 ---------------------------------------- (17) Obligation: Q DP problem: P is empty. The TRS R consists of the following rules: s(d(x1)) -> s(p(d(s(s(x1))))) s(f(x1)) -> s(p(f(d(x1)))) s(p(x1)) -> x1 The set Q consists of the following terms: s(d(x0)) s(f(x0)) s(p(x0)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (18) PisEmptyProof (EQUIVALENT) The TRS P is empty. Hence, there is no (P,Q,R) chain. ---------------------------------------- (19) YES ---------------------------------------- (20) Obligation: Q DP problem: The TRS P consists of the following rules: 0^1(d(x1)) -> 0^1(x1) The TRS R consists of the following rules: 0(d(x1)) -> 0(x1) s(d(x1)) -> s(p(d(s(s(x1))))) s(f(x1)) -> s(p(f(d(x1)))) s(p(x1)) -> x1 The set Q consists of the following terms: 0(d(x0)) s(d(x0)) s(f(x0)) s(p(x0)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (21) 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. ---------------------------------------- (22) Obligation: Q DP problem: The TRS P consists of the following rules: 0^1(d(x1)) -> 0^1(x1) R is empty. The set Q consists of the following terms: 0(d(x0)) s(d(x0)) s(f(x0)) s(p(x0)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (23) 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]. 0(d(x0)) s(d(x0)) s(f(x0)) s(p(x0)) ---------------------------------------- (24) Obligation: Q DP problem: The TRS P consists of the following rules: 0^1(d(x1)) -> 0^1(x1) R is empty. Q is empty. We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (25) QDPSizeChangeProof (EQUIVALENT) By using the subterm criterion [SUBTERM_CRITERION] together with the size-change analysis [AAECC05] we have proven that there are no infinite chains for this DP problem. From the DPs we obtained the following set of size-change graphs: *0^1(d(x1)) -> 0^1(x1) The graph contains the following edges 1 > 1 ---------------------------------------- (26) YES