/export/starexec/sandbox/solver/bin/starexec_run_standard /export/starexec/sandbox/benchmark/theBenchmark.xml /export/starexec/sandbox/output/output_files -------------------------------------------------------------------------------- YES proof of /export/starexec/sandbox/benchmark/theBenchmark.xml # AProVE Commit ID: 48fb2092695e11cc9f56e44b17a92a5f88ffb256 marcel 20180622 unpublished dirty Termination w.r.t. Q of the given QTRS could be proven: (0) QTRS (1) Overlay + Local Confluence [EQUIVALENT, 0 ms] (2) QTRS (3) DependencyPairsProof [EQUIVALENT, 6 ms] (4) QDP (5) DependencyGraphProof [EQUIVALENT, 0 ms] (6) AND (7) QDP (8) UsableRulesProof [EQUIVALENT, 0 ms] (9) QDP (10) QReductionProof [EQUIVALENT, 0 ms] (11) QDP (12) QDPSizeChangeProof [EQUIVALENT, 0 ms] (13) YES (14) QDP (15) UsableRulesProof [EQUIVALENT, 0 ms] (16) QDP (17) QReductionProof [EQUIVALENT, 0 ms] (18) QDP (19) QDPSizeChangeProof [EQUIVALENT, 0 ms] (20) YES (21) QDP (22) UsableRulesProof [EQUIVALENT, 0 ms] (23) QDP (24) QReductionProof [EQUIVALENT, 0 ms] (25) QDP (26) QDPOrderProof [EQUIVALENT, 0 ms] (27) QDP (28) PisEmptyProof [EQUIVALENT, 0 ms] (29) YES ---------------------------------------- (0) Obligation: Q restricted rewrite system: The TRS R consists of the following rules: -(x, 0) -> x -(0, s(y)) -> 0 -(s(x), s(y)) -> -(x, y) lt(x, 0) -> false lt(0, s(y)) -> true lt(s(x), s(y)) -> lt(x, y) if(true, x, y) -> x if(false, x, y) -> y div(x, 0) -> 0 div(0, y) -> 0 div(s(x), s(y)) -> if(lt(x, y), 0, s(div(-(x, y), s(y)))) Q is empty. ---------------------------------------- (1) Overlay + Local Confluence (EQUIVALENT) The TRS is overlay and locally confluent. By [NOC] we can switch to innermost. ---------------------------------------- (2) Obligation: Q restricted rewrite system: The TRS R consists of the following rules: -(x, 0) -> x -(0, s(y)) -> 0 -(s(x), s(y)) -> -(x, y) lt(x, 0) -> false lt(0, s(y)) -> true lt(s(x), s(y)) -> lt(x, y) if(true, x, y) -> x if(false, x, y) -> y div(x, 0) -> 0 div(0, y) -> 0 div(s(x), s(y)) -> if(lt(x, y), 0, s(div(-(x, y), s(y)))) The set Q consists of the following terms: -(x0, 0) -(0, s(x0)) -(s(x0), s(x1)) lt(x0, 0) lt(0, s(x0)) lt(s(x0), s(x1)) if(true, x0, x1) if(false, x0, x1) div(x0, 0) div(0, x0) div(s(x0), s(x1)) ---------------------------------------- (3) DependencyPairsProof (EQUIVALENT) Using Dependency Pairs [AG00,LPAR04] we result in the following initial DP problem. ---------------------------------------- (4) Obligation: Q DP problem: The TRS P consists of the following rules: -^1(s(x), s(y)) -> -^1(x, y) LT(s(x), s(y)) -> LT(x, y) DIV(s(x), s(y)) -> IF(lt(x, y), 0, s(div(-(x, y), s(y)))) DIV(s(x), s(y)) -> LT(x, y) DIV(s(x), s(y)) -> DIV(-(x, y), s(y)) DIV(s(x), s(y)) -> -^1(x, y) The TRS R consists of the following rules: -(x, 0) -> x -(0, s(y)) -> 0 -(s(x), s(y)) -> -(x, y) lt(x, 0) -> false lt(0, s(y)) -> true lt(s(x), s(y)) -> lt(x, y) if(true, x, y) -> x if(false, x, y) -> y div(x, 0) -> 0 div(0, y) -> 0 div(s(x), s(y)) -> if(lt(x, y), 0, s(div(-(x, y), s(y)))) The set Q consists of the following terms: -(x0, 0) -(0, s(x0)) -(s(x0), s(x1)) lt(x0, 0) lt(0, s(x0)) lt(s(x0), s(x1)) if(true, x0, x1) if(false, x0, x1) div(x0, 0) div(0, x0) div(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (5) DependencyGraphProof (EQUIVALENT) The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 3 SCCs with 3 less nodes. ---------------------------------------- (6) Complex Obligation (AND) ---------------------------------------- (7) Obligation: Q DP problem: The TRS P consists of the following rules: LT(s(x), s(y)) -> LT(x, y) The TRS R consists of the following rules: -(x, 0) -> x -(0, s(y)) -> 0 -(s(x), s(y)) -> -(x, y) lt(x, 0) -> false lt(0, s(y)) -> true lt(s(x), s(y)) -> lt(x, y) if(true, x, y) -> x if(false, x, y) -> y div(x, 0) -> 0 div(0, y) -> 0 div(s(x), s(y)) -> if(lt(x, y), 0, s(div(-(x, y), s(y)))) The set Q consists of the following terms: -(x0, 0) -(0, s(x0)) -(s(x0), s(x1)) lt(x0, 0) lt(0, s(x0)) lt(s(x0), s(x1)) if(true, x0, x1) if(false, x0, x1) div(x0, 0) div(0, x0) div(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (8) 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. ---------------------------------------- (9) Obligation: Q DP problem: The TRS P consists of the following rules: LT(s(x), s(y)) -> LT(x, y) R is empty. The set Q consists of the following terms: -(x0, 0) -(0, s(x0)) -(s(x0), s(x1)) lt(x0, 0) lt(0, s(x0)) lt(s(x0), s(x1)) if(true, x0, x1) if(false, x0, x1) div(x0, 0) div(0, x0) div(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (10) 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]. -(x0, 0) -(0, s(x0)) -(s(x0), s(x1)) lt(x0, 0) lt(0, s(x0)) lt(s(x0), s(x1)) if(true, x0, x1) if(false, x0, x1) div(x0, 0) div(0, x0) div(s(x0), s(x1)) ---------------------------------------- (11) Obligation: Q DP problem: The TRS P consists of the following rules: LT(s(x), s(y)) -> LT(x, y) R is empty. Q is empty. We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (12) 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: *LT(s(x), s(y)) -> LT(x, y) The graph contains the following edges 1 > 1, 2 > 2 ---------------------------------------- (13) YES ---------------------------------------- (14) Obligation: Q DP problem: The TRS P consists of the following rules: -^1(s(x), s(y)) -> -^1(x, y) The TRS R consists of the following rules: -(x, 0) -> x -(0, s(y)) -> 0 -(s(x), s(y)) -> -(x, y) lt(x, 0) -> false lt(0, s(y)) -> true lt(s(x), s(y)) -> lt(x, y) if(true, x, y) -> x if(false, x, y) -> y div(x, 0) -> 0 div(0, y) -> 0 div(s(x), s(y)) -> if(lt(x, y), 0, s(div(-(x, y), s(y)))) The set Q consists of the following terms: -(x0, 0) -(0, s(x0)) -(s(x0), s(x1)) lt(x0, 0) lt(0, s(x0)) lt(s(x0), s(x1)) if(true, x0, x1) if(false, x0, x1) div(x0, 0) div(0, x0) div(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (15) 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. ---------------------------------------- (16) Obligation: Q DP problem: The TRS P consists of the following rules: -^1(s(x), s(y)) -> -^1(x, y) R is empty. The set Q consists of the following terms: -(x0, 0) -(0, s(x0)) -(s(x0), s(x1)) lt(x0, 0) lt(0, s(x0)) lt(s(x0), s(x1)) if(true, x0, x1) if(false, x0, x1) div(x0, 0) div(0, x0) div(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (17) 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]. -(x0, 0) -(0, s(x0)) -(s(x0), s(x1)) lt(x0, 0) lt(0, s(x0)) lt(s(x0), s(x1)) if(true, x0, x1) if(false, x0, x1) div(x0, 0) div(0, x0) div(s(x0), s(x1)) ---------------------------------------- (18) Obligation: Q DP problem: The TRS P consists of the following rules: -^1(s(x), s(y)) -> -^1(x, y) R is empty. Q is empty. We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (19) 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: *-^1(s(x), s(y)) -> -^1(x, y) The graph contains the following edges 1 > 1, 2 > 2 ---------------------------------------- (20) YES ---------------------------------------- (21) Obligation: Q DP problem: The TRS P consists of the following rules: DIV(s(x), s(y)) -> DIV(-(x, y), s(y)) The TRS R consists of the following rules: -(x, 0) -> x -(0, s(y)) -> 0 -(s(x), s(y)) -> -(x, y) lt(x, 0) -> false lt(0, s(y)) -> true lt(s(x), s(y)) -> lt(x, y) if(true, x, y) -> x if(false, x, y) -> y div(x, 0) -> 0 div(0, y) -> 0 div(s(x), s(y)) -> if(lt(x, y), 0, s(div(-(x, y), s(y)))) The set Q consists of the following terms: -(x0, 0) -(0, s(x0)) -(s(x0), s(x1)) lt(x0, 0) lt(0, s(x0)) lt(s(x0), s(x1)) if(true, x0, x1) if(false, x0, x1) div(x0, 0) div(0, x0) div(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (22) 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. ---------------------------------------- (23) Obligation: Q DP problem: The TRS P consists of the following rules: DIV(s(x), s(y)) -> DIV(-(x, y), s(y)) The TRS R consists of the following rules: -(x, 0) -> x -(0, s(y)) -> 0 -(s(x), s(y)) -> -(x, y) The set Q consists of the following terms: -(x0, 0) -(0, s(x0)) -(s(x0), s(x1)) lt(x0, 0) lt(0, s(x0)) lt(s(x0), s(x1)) if(true, x0, x1) if(false, x0, x1) div(x0, 0) div(0, x0) div(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (24) 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]. lt(x0, 0) lt(0, s(x0)) lt(s(x0), s(x1)) if(true, x0, x1) if(false, x0, x1) div(x0, 0) div(0, x0) div(s(x0), s(x1)) ---------------------------------------- (25) Obligation: Q DP problem: The TRS P consists of the following rules: DIV(s(x), s(y)) -> DIV(-(x, y), s(y)) The TRS R consists of the following rules: -(x, 0) -> x -(0, s(y)) -> 0 -(s(x), s(y)) -> -(x, y) The set Q consists of the following terms: -(x0, 0) -(0, s(x0)) -(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (26) QDPOrderProof (EQUIVALENT) We use the reduction pair processor [LPAR04,JAR06]. The following pairs can be oriented strictly and are deleted. DIV(s(x), s(y)) -> DIV(-(x, y), s(y)) The remaining pairs can at least be oriented weakly. Used ordering: Combined order from the following AFS and order. DIV(x1, x2) = x1 s(x1) = s(x1) -(x1, x2) = x1 0 = 0 Knuth-Bendix order [KBO] with precedence:trivial and weight map: s_1=1 0=1 The following usable rules [FROCOS05] with respect to the argument filtering of the ordering [JAR06] were oriented: -(x, 0) -> x -(0, s(y)) -> 0 -(s(x), s(y)) -> -(x, y) ---------------------------------------- (27) Obligation: Q DP problem: P is empty. The TRS R consists of the following rules: -(x, 0) -> x -(0, s(y)) -> 0 -(s(x), s(y)) -> -(x, y) The set Q consists of the following terms: -(x0, 0) -(0, s(x0)) -(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (28) PisEmptyProof (EQUIVALENT) The TRS P is empty. Hence, there is no (P,Q,R) chain. ---------------------------------------- (29) YES