/export/starexec/sandbox/solver/bin/starexec_run_standard /export/starexec/sandbox/benchmark/theBenchmark.xml /export/starexec/sandbox/output/output_files -------------------------------------------------------------------------------- NO 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# AProVE Commit ID: 48fb2092695e11cc9f56e44b17a92a5f88ffb256 marcel 20180622 unpublished dirty Termination w.r.t. Q of the given QTRS could be disproven: (0) QTRS (1) Overlay + Local Confluence [EQUIVALENT, 14 ms] (2) QTRS (3) DependencyPairsProof [EQUIVALENT, 0 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) QDPOrderProof [EQUIVALENT, 50 ms] (13) QDP (14) PisEmptyProof [EQUIVALENT, 0 ms] (15) YES (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) NonTerminationLoopProof [COMPLETE, 0 ms] (26) NO ---------------------------------------- (0) Obligation: Q restricted rewrite system: The TRS R consists of the following rules: primes -> sieve(from(s(s(0)))) from(X) -> cons(X, from(s(X))) head(cons(X, Y)) -> X tail(cons(X, Y)) -> Y if(true, X, Y) -> X if(false, X, Y) -> Y filter(s(s(X)), cons(Y, Z)) -> if(divides(s(s(X)), Y), filter(s(s(X)), Z), cons(Y, filter(X, sieve(Y)))) sieve(cons(X, Y)) -> cons(X, filter(X, sieve(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: primes -> sieve(from(s(s(0)))) from(X) -> cons(X, from(s(X))) head(cons(X, Y)) -> X tail(cons(X, Y)) -> Y if(true, X, Y) -> X if(false, X, Y) -> Y filter(s(s(X)), cons(Y, Z)) -> if(divides(s(s(X)), Y), filter(s(s(X)), Z), cons(Y, filter(X, sieve(Y)))) sieve(cons(X, Y)) -> cons(X, filter(X, sieve(Y))) The set Q consists of the following terms: primes from(x0) head(cons(x0, x1)) tail(cons(x0, x1)) if(true, x0, x1) if(false, x0, x1) filter(s(s(x0)), cons(x1, x2)) sieve(cons(x0, 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: PRIMES -> SIEVE(from(s(s(0)))) PRIMES -> FROM(s(s(0))) FROM(X) -> FROM(s(X)) FILTER(s(s(X)), cons(Y, Z)) -> IF(divides(s(s(X)), Y), filter(s(s(X)), Z), cons(Y, filter(X, sieve(Y)))) FILTER(s(s(X)), cons(Y, Z)) -> FILTER(s(s(X)), Z) FILTER(s(s(X)), cons(Y, Z)) -> FILTER(X, sieve(Y)) FILTER(s(s(X)), cons(Y, Z)) -> SIEVE(Y) SIEVE(cons(X, Y)) -> FILTER(X, sieve(Y)) SIEVE(cons(X, Y)) -> SIEVE(Y) The TRS R consists of the following rules: primes -> sieve(from(s(s(0)))) from(X) -> cons(X, from(s(X))) head(cons(X, Y)) -> X tail(cons(X, Y)) -> Y if(true, X, Y) -> X if(false, X, Y) -> Y filter(s(s(X)), cons(Y, Z)) -> if(divides(s(s(X)), Y), filter(s(s(X)), Z), cons(Y, filter(X, sieve(Y)))) sieve(cons(X, Y)) -> cons(X, filter(X, sieve(Y))) The set Q consists of the following terms: primes from(x0) head(cons(x0, x1)) tail(cons(x0, x1)) if(true, x0, x1) if(false, x0, x1) filter(s(s(x0)), cons(x1, x2)) sieve(cons(x0, x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (5) DependencyGraphProof (EQUIVALENT) The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 2 SCCs with 3 less nodes. ---------------------------------------- (6) Complex Obligation (AND) ---------------------------------------- (7) Obligation: Q DP problem: The TRS P consists of the following rules: FILTER(s(s(X)), cons(Y, Z)) -> FILTER(X, sieve(Y)) FILTER(s(s(X)), cons(Y, Z)) -> FILTER(s(s(X)), Z) FILTER(s(s(X)), cons(Y, Z)) -> SIEVE(Y) SIEVE(cons(X, Y)) -> FILTER(X, sieve(Y)) SIEVE(cons(X, Y)) -> SIEVE(Y) The TRS R consists of the following rules: primes -> sieve(from(s(s(0)))) from(X) -> cons(X, from(s(X))) head(cons(X, Y)) -> X tail(cons(X, Y)) -> Y if(true, X, Y) -> X if(false, X, Y) -> Y filter(s(s(X)), cons(Y, Z)) -> if(divides(s(s(X)), Y), filter(s(s(X)), Z), cons(Y, filter(X, sieve(Y)))) sieve(cons(X, Y)) -> cons(X, filter(X, sieve(Y))) The set Q consists of the following terms: primes from(x0) head(cons(x0, x1)) tail(cons(x0, x1)) if(true, x0, x1) if(false, x0, x1) filter(s(s(x0)), cons(x1, x2)) sieve(cons(x0, 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: FILTER(s(s(X)), cons(Y, Z)) -> FILTER(X, sieve(Y)) FILTER(s(s(X)), cons(Y, Z)) -> FILTER(s(s(X)), Z) FILTER(s(s(X)), cons(Y, Z)) -> SIEVE(Y) SIEVE(cons(X, Y)) -> FILTER(X, sieve(Y)) SIEVE(cons(X, Y)) -> SIEVE(Y) The TRS R consists of the following rules: sieve(cons(X, Y)) -> cons(X, filter(X, sieve(Y))) filter(s(s(X)), cons(Y, Z)) -> if(divides(s(s(X)), Y), filter(s(s(X)), Z), cons(Y, filter(X, sieve(Y)))) The set Q consists of the following terms: primes from(x0) head(cons(x0, x1)) tail(cons(x0, x1)) if(true, x0, x1) if(false, x0, x1) filter(s(s(x0)), cons(x1, x2)) sieve(cons(x0, 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]. primes from(x0) head(cons(x0, x1)) tail(cons(x0, x1)) ---------------------------------------- (11) Obligation: Q DP problem: The TRS P consists of the following rules: FILTER(s(s(X)), cons(Y, Z)) -> FILTER(X, sieve(Y)) FILTER(s(s(X)), cons(Y, Z)) -> FILTER(s(s(X)), Z) FILTER(s(s(X)), cons(Y, Z)) -> SIEVE(Y) SIEVE(cons(X, Y)) -> FILTER(X, sieve(Y)) SIEVE(cons(X, Y)) -> SIEVE(Y) The TRS R consists of the following rules: sieve(cons(X, Y)) -> cons(X, filter(X, sieve(Y))) filter(s(s(X)), cons(Y, Z)) -> if(divides(s(s(X)), Y), filter(s(s(X)), Z), cons(Y, filter(X, sieve(Y)))) The set Q consists of the following terms: if(true, x0, x1) if(false, x0, x1) filter(s(s(x0)), cons(x1, x2)) sieve(cons(x0, x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (12) QDPOrderProof (EQUIVALENT) We use the reduction pair processor [LPAR04,JAR06]. The following pairs can be oriented strictly and are deleted. FILTER(s(s(X)), cons(Y, Z)) -> FILTER(X, sieve(Y)) FILTER(s(s(X)), cons(Y, Z)) -> FILTER(s(s(X)), Z) FILTER(s(s(X)), cons(Y, Z)) -> SIEVE(Y) SIEVE(cons(X, Y)) -> FILTER(X, sieve(Y)) SIEVE(cons(X, Y)) -> SIEVE(Y) The remaining pairs can at least be oriented weakly. Used ordering: Polynomial Order [NEGPOLO,POLO] with Interpretation: POL( FILTER_2(x_1, x_2) ) = max{0, 2x_1 + 2x_2 - 2} POL( sieve_1(x_1) ) = x_1 POL( cons_2(x_1, x_2) ) = 2x_1 + x_2 + 2 POL( filter_2(x_1, x_2) ) = max{0, -2} POL( s_1(x_1) ) = x_1 + 1 POL( if_3(x_1, ..., x_3) ) = max{0, -2} POL( divides_2(x_1, x_2) ) = max{0, 2x_2 - 2} POL( SIEVE_1(x_1) ) = 2x_1 + 2 The following usable rules [FROCOS05] with respect to the argument filtering of the ordering [JAR06] were oriented: sieve(cons(X, Y)) -> cons(X, filter(X, sieve(Y))) filter(s(s(X)), cons(Y, Z)) -> if(divides(s(s(X)), Y), filter(s(s(X)), Z), cons(Y, filter(X, sieve(Y)))) ---------------------------------------- (13) Obligation: Q DP problem: P is empty. The TRS R consists of the following rules: sieve(cons(X, Y)) -> cons(X, filter(X, sieve(Y))) filter(s(s(X)), cons(Y, Z)) -> if(divides(s(s(X)), Y), filter(s(s(X)), Z), cons(Y, filter(X, sieve(Y)))) The set Q consists of the following terms: if(true, x0, x1) if(false, x0, x1) filter(s(s(x0)), cons(x1, x2)) sieve(cons(x0, x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (14) PisEmptyProof (EQUIVALENT) The TRS P is empty. Hence, there is no (P,Q,R) chain. ---------------------------------------- (15) YES ---------------------------------------- (16) Obligation: Q DP problem: The TRS P consists of the following rules: FROM(X) -> FROM(s(X)) The TRS R consists of the following rules: primes -> sieve(from(s(s(0)))) from(X) -> cons(X, from(s(X))) head(cons(X, Y)) -> X tail(cons(X, Y)) -> Y if(true, X, Y) -> X if(false, X, Y) -> Y filter(s(s(X)), cons(Y, Z)) -> if(divides(s(s(X)), Y), filter(s(s(X)), Z), cons(Y, filter(X, sieve(Y)))) sieve(cons(X, Y)) -> cons(X, filter(X, sieve(Y))) The set Q consists of the following terms: primes from(x0) head(cons(x0, x1)) tail(cons(x0, x1)) if(true, x0, x1) if(false, x0, x1) filter(s(s(x0)), cons(x1, x2)) sieve(cons(x0, x1)) 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: FROM(X) -> FROM(s(X)) R is empty. The set Q consists of the following terms: primes from(x0) head(cons(x0, x1)) tail(cons(x0, x1)) if(true, x0, x1) if(false, x0, x1) filter(s(s(x0)), cons(x1, x2)) sieve(cons(x0, x1)) 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]. primes from(x0) head(cons(x0, x1)) tail(cons(x0, x1)) if(true, x0, x1) if(false, x0, x1) filter(s(s(x0)), cons(x1, x2)) sieve(cons(x0, x1)) ---------------------------------------- (20) Obligation: Q DP problem: The TRS P consists of the following rules: FROM(X) -> FROM(s(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 FROM(X) -> FROM(s(X)) we obtained the following new rules [LPAR04]: (FROM(s(z0)) -> FROM(s(s(z0))),FROM(s(z0)) -> FROM(s(s(z0)))) ---------------------------------------- (22) Obligation: Q DP problem: The TRS P consists of the following rules: FROM(s(z0)) -> FROM(s(s(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 FROM(s(z0)) -> FROM(s(s(z0))) we obtained the following new rules [LPAR04]: (FROM(s(s(z0))) -> FROM(s(s(s(z0)))),FROM(s(s(z0))) -> FROM(s(s(s(z0))))) ---------------------------------------- (24) Obligation: Q DP problem: The TRS P consists of the following rules: FROM(s(s(z0))) -> FROM(s(s(s(z0)))) R is empty. Q is empty. We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (25) NonTerminationLoopProof (COMPLETE) We used the non-termination processor [FROCOS05] to show that the DP problem is infinite. Found a loop by semiunifying a rule from P directly. s = FROM(s(s(z0))) evaluates to t =FROM(s(s(s(z0)))) Thus s starts an infinite chain as s semiunifies with t with the following substitutions: * Matcher: [z0 / s(z0)] * Semiunifier: [ ] -------------------------------------------------------------------------------- Rewriting sequence The DP semiunifies directly so there is only one rewrite step from FROM(s(s(z0))) to FROM(s(s(s(z0)))). ---------------------------------------- (26) NO