/export/starexec/sandbox2/solver/bin/starexec_run_standard /export/starexec/sandbox2/benchmark/theBenchmark.xml /export/starexec/sandbox2/output/output_files -------------------------------------------------------------------------------- YES proof of /export/starexec/sandbox2/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# AProVE Commit ID: 48fb2092695e11cc9f56e44b17a92a5f88ffb256 marcel 20180622 unpublished dirty Termination w.r.t. Q of the given QTRS could be proven: (0) QTRS (1) Overlay + Local Confluence [EQUIVALENT, 14 ms] (2) QTRS (3) DependencyPairsProof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) 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) TransformationProof [EQUIVALENT, 0 ms] (27) QDP (28) DependencyGraphProof [EQUIVALENT, 0 ms] (29) QDP (30) TransformationProof [EQUIVALENT, 0 ms] (31) QDP (32) TransformationProof [EQUIVALENT, 0 ms] (33) QDP (34) DependencyGraphProof [EQUIVALENT, 0 ms] (35) QDP (36) TransformationProof [EQUIVALENT, 0 ms] (37) QDP (38) TransformationProof [EQUIVALENT, 0 ms] (39) QDP (40) TransformationProof [EQUIVALENT, 0 ms] (41) QDP (42) TransformationProof [EQUIVALENT, 0 ms] (43) QDP (44) TransformationProof [EQUIVALENT, 0 ms] (45) QDP (46) TransformationProof [EQUIVALENT, 0 ms] (47) QDP (48) DependencyGraphProof [EQUIVALENT, 0 ms] (49) AND (50) QDP (51) TransformationProof [EQUIVALENT, 0 ms] (52) QDP (53) TransformationProof [EQUIVALENT, 0 ms] (54) QDP (55) QDPOrderProof [EQUIVALENT, 12 ms] (56) QDP (57) PisEmptyProof [EQUIVALENT, 0 ms] (58) YES (59) QDP (60) UsableRulesProof [EQUIVALENT, 0 ms] (61) QDP (62) QReductionProof [EQUIVALENT, 0 ms] (63) QDP (64) TransformationProof [EQUIVALENT, 0 ms] (65) QDP (66) UsableRulesProof [EQUIVALENT, 0 ms] (67) QDP (68) QReductionProof [EQUIVALENT, 0 ms] (69) QDP (70) TransformationProof [EQUIVALENT, 0 ms] (71) QDP (72) TransformationProof [EQUIVALENT, 0 ms] (73) QDP (74) QDPSizeChangeProof [EQUIVALENT, 0 ms] (75) YES ---------------------------------------- (0) Obligation: Q restricted rewrite system: The TRS R consists of the following rules: ge(x, 0) -> true ge(0, s(x)) -> false ge(s(x), s(y)) -> ge(x, y) minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) div(x, y) -> ify(ge(y, s(0)), x, y) ify(false, x, y) -> divByZeroError ify(true, x, y) -> if(ge(x, y), x, y) if(false, x, y) -> 0 if(true, x, y) -> s(div(minus(x, y), 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: ge(x, 0) -> true ge(0, s(x)) -> false ge(s(x), s(y)) -> ge(x, y) minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) div(x, y) -> ify(ge(y, s(0)), x, y) ify(false, x, y) -> divByZeroError ify(true, x, y) -> if(ge(x, y), x, y) if(false, x, y) -> 0 if(true, x, y) -> s(div(minus(x, y), y)) The set Q consists of the following terms: ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) minus(x0, 0) minus(s(x0), s(x1)) div(x0, x1) ify(false, x0, x1) ify(true, x0, x1) if(false, x0, x1) if(true, 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: GE(s(x), s(y)) -> GE(x, y) MINUS(s(x), s(y)) -> MINUS(x, y) DIV(x, y) -> IFY(ge(y, s(0)), x, y) DIV(x, y) -> GE(y, s(0)) IFY(true, x, y) -> IF(ge(x, y), x, y) IFY(true, x, y) -> GE(x, y) IF(true, x, y) -> DIV(minus(x, y), y) IF(true, x, y) -> MINUS(x, y) The TRS R consists of the following rules: ge(x, 0) -> true ge(0, s(x)) -> false ge(s(x), s(y)) -> ge(x, y) minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) div(x, y) -> ify(ge(y, s(0)), x, y) ify(false, x, y) -> divByZeroError ify(true, x, y) -> if(ge(x, y), x, y) if(false, x, y) -> 0 if(true, x, y) -> s(div(minus(x, y), y)) The set Q consists of the following terms: ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) minus(x0, 0) minus(s(x0), s(x1)) div(x0, x1) ify(false, x0, x1) ify(true, x0, x1) if(false, x0, x1) if(true, 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 3 SCCs with 3 less nodes. ---------------------------------------- (6) Complex Obligation (AND) ---------------------------------------- (7) Obligation: Q DP problem: The TRS P consists of the following rules: MINUS(s(x), s(y)) -> MINUS(x, y) The TRS R consists of the following rules: ge(x, 0) -> true ge(0, s(x)) -> false ge(s(x), s(y)) -> ge(x, y) minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) div(x, y) -> ify(ge(y, s(0)), x, y) ify(false, x, y) -> divByZeroError ify(true, x, y) -> if(ge(x, y), x, y) if(false, x, y) -> 0 if(true, x, y) -> s(div(minus(x, y), y)) The set Q consists of the following terms: ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) minus(x0, 0) minus(s(x0), s(x1)) div(x0, x1) ify(false, x0, x1) ify(true, x0, x1) if(false, x0, x1) if(true, 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: MINUS(s(x), s(y)) -> MINUS(x, y) R is empty. The set Q consists of the following terms: ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) minus(x0, 0) minus(s(x0), s(x1)) div(x0, x1) ify(false, x0, x1) ify(true, x0, x1) if(false, x0, x1) if(true, 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]. ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) minus(x0, 0) minus(s(x0), s(x1)) div(x0, x1) ify(false, x0, x1) ify(true, x0, x1) if(false, x0, x1) if(true, x0, x1) ---------------------------------------- (11) Obligation: Q DP problem: The TRS P consists of the following rules: MINUS(s(x), s(y)) -> MINUS(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: *MINUS(s(x), s(y)) -> MINUS(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: GE(s(x), s(y)) -> GE(x, y) The TRS R consists of the following rules: ge(x, 0) -> true ge(0, s(x)) -> false ge(s(x), s(y)) -> ge(x, y) minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) div(x, y) -> ify(ge(y, s(0)), x, y) ify(false, x, y) -> divByZeroError ify(true, x, y) -> if(ge(x, y), x, y) if(false, x, y) -> 0 if(true, x, y) -> s(div(minus(x, y), y)) The set Q consists of the following terms: ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) minus(x0, 0) minus(s(x0), s(x1)) div(x0, x1) ify(false, x0, x1) ify(true, x0, x1) if(false, x0, x1) if(true, x0, 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: GE(s(x), s(y)) -> GE(x, y) R is empty. The set Q consists of the following terms: ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) minus(x0, 0) minus(s(x0), s(x1)) div(x0, x1) ify(false, x0, x1) ify(true, x0, x1) if(false, x0, x1) if(true, x0, 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]. ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) minus(x0, 0) minus(s(x0), s(x1)) div(x0, x1) ify(false, x0, x1) ify(true, x0, x1) if(false, x0, x1) if(true, x0, x1) ---------------------------------------- (18) Obligation: Q DP problem: The TRS P consists of the following rules: GE(s(x), s(y)) -> GE(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: *GE(s(x), s(y)) -> GE(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(x, y) -> IFY(ge(y, s(0)), x, y) IFY(true, x, y) -> IF(ge(x, y), x, y) IF(true, x, y) -> DIV(minus(x, y), y) The TRS R consists of the following rules: ge(x, 0) -> true ge(0, s(x)) -> false ge(s(x), s(y)) -> ge(x, y) minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) div(x, y) -> ify(ge(y, s(0)), x, y) ify(false, x, y) -> divByZeroError ify(true, x, y) -> if(ge(x, y), x, y) if(false, x, y) -> 0 if(true, x, y) -> s(div(minus(x, y), y)) The set Q consists of the following terms: ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) minus(x0, 0) minus(s(x0), s(x1)) div(x0, x1) ify(false, x0, x1) ify(true, x0, x1) if(false, x0, x1) if(true, x0, 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(x, y) -> IFY(ge(y, s(0)), x, y) IFY(true, x, y) -> IF(ge(x, y), x, y) IF(true, x, y) -> DIV(minus(x, y), y) The TRS R consists of the following rules: minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) ge(x, 0) -> true ge(0, s(x)) -> false ge(s(x), s(y)) -> ge(x, y) The set Q consists of the following terms: ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) minus(x0, 0) minus(s(x0), s(x1)) div(x0, x1) ify(false, x0, x1) ify(true, x0, x1) if(false, x0, x1) if(true, x0, 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]. div(x0, x1) ify(false, x0, x1) ify(true, x0, x1) if(false, x0, x1) if(true, x0, x1) ---------------------------------------- (25) Obligation: Q DP problem: The TRS P consists of the following rules: DIV(x, y) -> IFY(ge(y, s(0)), x, y) IFY(true, x, y) -> IF(ge(x, y), x, y) IF(true, x, y) -> DIV(minus(x, y), y) The TRS R consists of the following rules: minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) ge(x, 0) -> true ge(0, s(x)) -> false ge(s(x), s(y)) -> ge(x, y) The set Q consists of the following terms: ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) minus(x0, 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (26) TransformationProof (EQUIVALENT) By narrowing [LPAR04] the rule DIV(x, y) -> IFY(ge(y, s(0)), x, y) at position [0] we obtained the following new rules [LPAR04]: (DIV(y0, 0) -> IFY(false, y0, 0),DIV(y0, 0) -> IFY(false, y0, 0)) (DIV(y0, s(x0)) -> IFY(ge(x0, 0), y0, s(x0)),DIV(y0, s(x0)) -> IFY(ge(x0, 0), y0, s(x0))) ---------------------------------------- (27) Obligation: Q DP problem: The TRS P consists of the following rules: IFY(true, x, y) -> IF(ge(x, y), x, y) IF(true, x, y) -> DIV(minus(x, y), y) DIV(y0, 0) -> IFY(false, y0, 0) DIV(y0, s(x0)) -> IFY(ge(x0, 0), y0, s(x0)) The TRS R consists of the following rules: minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) ge(x, 0) -> true ge(0, s(x)) -> false ge(s(x), s(y)) -> ge(x, y) The set Q consists of the following terms: ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) minus(x0, 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (28) DependencyGraphProof (EQUIVALENT) The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 1 SCC with 1 less node. ---------------------------------------- (29) Obligation: Q DP problem: The TRS P consists of the following rules: IF(true, x, y) -> DIV(minus(x, y), y) DIV(y0, s(x0)) -> IFY(ge(x0, 0), y0, s(x0)) IFY(true, x, y) -> IF(ge(x, y), x, y) The TRS R consists of the following rules: minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) ge(x, 0) -> true ge(0, s(x)) -> false ge(s(x), s(y)) -> ge(x, y) The set Q consists of the following terms: ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) minus(x0, 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (30) TransformationProof (EQUIVALENT) By rewriting [LPAR04] the rule DIV(y0, s(x0)) -> IFY(ge(x0, 0), y0, s(x0)) at position [0] we obtained the following new rules [LPAR04]: (DIV(y0, s(x0)) -> IFY(true, y0, s(x0)),DIV(y0, s(x0)) -> IFY(true, y0, s(x0))) ---------------------------------------- (31) Obligation: Q DP problem: The TRS P consists of the following rules: IF(true, x, y) -> DIV(minus(x, y), y) IFY(true, x, y) -> IF(ge(x, y), x, y) DIV(y0, s(x0)) -> IFY(true, y0, s(x0)) The TRS R consists of the following rules: minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) ge(x, 0) -> true ge(0, s(x)) -> false ge(s(x), s(y)) -> ge(x, y) The set Q consists of the following terms: ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) minus(x0, 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (32) TransformationProof (EQUIVALENT) By narrowing [LPAR04] the rule IFY(true, x, y) -> IF(ge(x, y), x, y) at position [0] we obtained the following new rules [LPAR04]: (IFY(true, x0, 0) -> IF(true, x0, 0),IFY(true, x0, 0) -> IF(true, x0, 0)) (IFY(true, 0, s(x0)) -> IF(false, 0, s(x0)),IFY(true, 0, s(x0)) -> IF(false, 0, s(x0))) (IFY(true, s(x0), s(x1)) -> IF(ge(x0, x1), s(x0), s(x1)),IFY(true, s(x0), s(x1)) -> IF(ge(x0, x1), s(x0), s(x1))) ---------------------------------------- (33) Obligation: Q DP problem: The TRS P consists of the following rules: IF(true, x, y) -> DIV(minus(x, y), y) DIV(y0, s(x0)) -> IFY(true, y0, s(x0)) IFY(true, x0, 0) -> IF(true, x0, 0) IFY(true, 0, s(x0)) -> IF(false, 0, s(x0)) IFY(true, s(x0), s(x1)) -> IF(ge(x0, x1), s(x0), s(x1)) The TRS R consists of the following rules: minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) ge(x, 0) -> true ge(0, s(x)) -> false ge(s(x), s(y)) -> ge(x, y) The set Q consists of the following terms: ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) minus(x0, 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (34) DependencyGraphProof (EQUIVALENT) The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 1 SCC with 2 less nodes. ---------------------------------------- (35) Obligation: Q DP problem: The TRS P consists of the following rules: DIV(y0, s(x0)) -> IFY(true, y0, s(x0)) IFY(true, s(x0), s(x1)) -> IF(ge(x0, x1), s(x0), s(x1)) IF(true, x, y) -> DIV(minus(x, y), y) The TRS R consists of the following rules: minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) ge(x, 0) -> true ge(0, s(x)) -> false ge(s(x), s(y)) -> ge(x, y) The set Q consists of the following terms: ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) minus(x0, 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (36) TransformationProof (EQUIVALENT) By instantiating [LPAR04] the rule IF(true, x, y) -> DIV(minus(x, y), y) we obtained the following new rules [LPAR04]: (IF(true, s(z0), s(z1)) -> DIV(minus(s(z0), s(z1)), s(z1)),IF(true, s(z0), s(z1)) -> DIV(minus(s(z0), s(z1)), s(z1))) ---------------------------------------- (37) Obligation: Q DP problem: The TRS P consists of the following rules: DIV(y0, s(x0)) -> IFY(true, y0, s(x0)) IFY(true, s(x0), s(x1)) -> IF(ge(x0, x1), s(x0), s(x1)) IF(true, s(z0), s(z1)) -> DIV(minus(s(z0), s(z1)), s(z1)) The TRS R consists of the following rules: minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) ge(x, 0) -> true ge(0, s(x)) -> false ge(s(x), s(y)) -> ge(x, y) The set Q consists of the following terms: ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) minus(x0, 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (38) TransformationProof (EQUIVALENT) By rewriting [LPAR04] the rule IF(true, s(z0), s(z1)) -> DIV(minus(s(z0), s(z1)), s(z1)) at position [0] we obtained the following new rules [LPAR04]: (IF(true, s(z0), s(z1)) -> DIV(minus(z0, z1), s(z1)),IF(true, s(z0), s(z1)) -> DIV(minus(z0, z1), s(z1))) ---------------------------------------- (39) Obligation: Q DP problem: The TRS P consists of the following rules: DIV(y0, s(x0)) -> IFY(true, y0, s(x0)) IFY(true, s(x0), s(x1)) -> IF(ge(x0, x1), s(x0), s(x1)) IF(true, s(z0), s(z1)) -> DIV(minus(z0, z1), s(z1)) The TRS R consists of the following rules: minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) ge(x, 0) -> true ge(0, s(x)) -> false ge(s(x), s(y)) -> ge(x, y) The set Q consists of the following terms: ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) minus(x0, 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (40) TransformationProof (EQUIVALENT) By forward instantiating [JAR06] the rule DIV(y0, s(x0)) -> IFY(true, y0, s(x0)) we obtained the following new rules [LPAR04]: (DIV(s(y_0), s(x1)) -> IFY(true, s(y_0), s(x1)),DIV(s(y_0), s(x1)) -> IFY(true, s(y_0), s(x1))) ---------------------------------------- (41) Obligation: Q DP problem: The TRS P consists of the following rules: IFY(true, s(x0), s(x1)) -> IF(ge(x0, x1), s(x0), s(x1)) IF(true, s(z0), s(z1)) -> DIV(minus(z0, z1), s(z1)) DIV(s(y_0), s(x1)) -> IFY(true, s(y_0), s(x1)) The TRS R consists of the following rules: minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) ge(x, 0) -> true ge(0, s(x)) -> false ge(s(x), s(y)) -> ge(x, y) The set Q consists of the following terms: ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) minus(x0, 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (42) TransformationProof (EQUIVALENT) By narrowing [LPAR04] the rule IF(true, s(z0), s(z1)) -> DIV(minus(z0, z1), s(z1)) at position [0] we obtained the following new rules [LPAR04]: (IF(true, s(x0), s(0)) -> DIV(x0, s(0)),IF(true, s(x0), s(0)) -> DIV(x0, s(0))) (IF(true, s(s(x0)), s(s(x1))) -> DIV(minus(x0, x1), s(s(x1))),IF(true, s(s(x0)), s(s(x1))) -> DIV(minus(x0, x1), s(s(x1)))) ---------------------------------------- (43) Obligation: Q DP problem: The TRS P consists of the following rules: IFY(true, s(x0), s(x1)) -> IF(ge(x0, x1), s(x0), s(x1)) DIV(s(y_0), s(x1)) -> IFY(true, s(y_0), s(x1)) IF(true, s(x0), s(0)) -> DIV(x0, s(0)) IF(true, s(s(x0)), s(s(x1))) -> DIV(minus(x0, x1), s(s(x1))) The TRS R consists of the following rules: minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) ge(x, 0) -> true ge(0, s(x)) -> false ge(s(x), s(y)) -> ge(x, y) The set Q consists of the following terms: ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) minus(x0, 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (44) TransformationProof (EQUIVALENT) By instantiating [LPAR04] the rule DIV(s(y_0), s(x1)) -> IFY(true, s(y_0), s(x1)) we obtained the following new rules [LPAR04]: (DIV(s(x0), s(0)) -> IFY(true, s(x0), s(0)),DIV(s(x0), s(0)) -> IFY(true, s(x0), s(0))) (DIV(s(x0), s(s(z1))) -> IFY(true, s(x0), s(s(z1))),DIV(s(x0), s(s(z1))) -> IFY(true, s(x0), s(s(z1)))) ---------------------------------------- (45) Obligation: Q DP problem: The TRS P consists of the following rules: IFY(true, s(x0), s(x1)) -> IF(ge(x0, x1), s(x0), s(x1)) IF(true, s(x0), s(0)) -> DIV(x0, s(0)) IF(true, s(s(x0)), s(s(x1))) -> DIV(minus(x0, x1), s(s(x1))) DIV(s(x0), s(0)) -> IFY(true, s(x0), s(0)) DIV(s(x0), s(s(z1))) -> IFY(true, s(x0), s(s(z1))) The TRS R consists of the following rules: minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) ge(x, 0) -> true ge(0, s(x)) -> false ge(s(x), s(y)) -> ge(x, y) The set Q consists of the following terms: ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) minus(x0, 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (46) TransformationProof (EQUIVALENT) By instantiating [LPAR04] the rule IFY(true, s(x0), s(x1)) -> IF(ge(x0, x1), s(x0), s(x1)) we obtained the following new rules [LPAR04]: (IFY(true, s(z0), s(0)) -> IF(ge(z0, 0), s(z0), s(0)),IFY(true, s(z0), s(0)) -> IF(ge(z0, 0), s(z0), s(0))) (IFY(true, s(z0), s(s(z1))) -> IF(ge(z0, s(z1)), s(z0), s(s(z1))),IFY(true, s(z0), s(s(z1))) -> IF(ge(z0, s(z1)), s(z0), s(s(z1)))) ---------------------------------------- (47) Obligation: Q DP problem: The TRS P consists of the following rules: IF(true, s(x0), s(0)) -> DIV(x0, s(0)) IF(true, s(s(x0)), s(s(x1))) -> DIV(minus(x0, x1), s(s(x1))) DIV(s(x0), s(0)) -> IFY(true, s(x0), s(0)) DIV(s(x0), s(s(z1))) -> IFY(true, s(x0), s(s(z1))) IFY(true, s(z0), s(0)) -> IF(ge(z0, 0), s(z0), s(0)) IFY(true, s(z0), s(s(z1))) -> IF(ge(z0, s(z1)), s(z0), s(s(z1))) The TRS R consists of the following rules: minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) ge(x, 0) -> true ge(0, s(x)) -> false ge(s(x), s(y)) -> ge(x, y) The set Q consists of the following terms: ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) minus(x0, 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (48) DependencyGraphProof (EQUIVALENT) The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 2 SCCs. ---------------------------------------- (49) Complex Obligation (AND) ---------------------------------------- (50) Obligation: Q DP problem: The TRS P consists of the following rules: DIV(s(x0), s(s(z1))) -> IFY(true, s(x0), s(s(z1))) IFY(true, s(z0), s(s(z1))) -> IF(ge(z0, s(z1)), s(z0), s(s(z1))) IF(true, s(s(x0)), s(s(x1))) -> DIV(minus(x0, x1), s(s(x1))) The TRS R consists of the following rules: minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) ge(x, 0) -> true ge(0, s(x)) -> false ge(s(x), s(y)) -> ge(x, y) The set Q consists of the following terms: ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) minus(x0, 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (51) TransformationProof (EQUIVALENT) By forward instantiating [JAR06] the rule IFY(true, s(z0), s(s(z1))) -> IF(ge(z0, s(z1)), s(z0), s(s(z1))) we obtained the following new rules [LPAR04]: (IFY(true, s(s(y_1)), s(s(x1))) -> IF(ge(s(y_1), s(x1)), s(s(y_1)), s(s(x1))),IFY(true, s(s(y_1)), s(s(x1))) -> IF(ge(s(y_1), s(x1)), s(s(y_1)), s(s(x1)))) ---------------------------------------- (52) Obligation: Q DP problem: The TRS P consists of the following rules: DIV(s(x0), s(s(z1))) -> IFY(true, s(x0), s(s(z1))) IF(true, s(s(x0)), s(s(x1))) -> DIV(minus(x0, x1), s(s(x1))) IFY(true, s(s(y_1)), s(s(x1))) -> IF(ge(s(y_1), s(x1)), s(s(y_1)), s(s(x1))) The TRS R consists of the following rules: minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) ge(x, 0) -> true ge(0, s(x)) -> false ge(s(x), s(y)) -> ge(x, y) The set Q consists of the following terms: ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) minus(x0, 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (53) TransformationProof (EQUIVALENT) By rewriting [LPAR04] the rule IFY(true, s(s(y_1)), s(s(x1))) -> IF(ge(s(y_1), s(x1)), s(s(y_1)), s(s(x1))) at position [0] we obtained the following new rules [LPAR04]: (IFY(true, s(s(y_1)), s(s(x1))) -> IF(ge(y_1, x1), s(s(y_1)), s(s(x1))),IFY(true, s(s(y_1)), s(s(x1))) -> IF(ge(y_1, x1), s(s(y_1)), s(s(x1)))) ---------------------------------------- (54) Obligation: Q DP problem: The TRS P consists of the following rules: DIV(s(x0), s(s(z1))) -> IFY(true, s(x0), s(s(z1))) IF(true, s(s(x0)), s(s(x1))) -> DIV(minus(x0, x1), s(s(x1))) IFY(true, s(s(y_1)), s(s(x1))) -> IF(ge(y_1, x1), s(s(y_1)), s(s(x1))) The TRS R consists of the following rules: minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) ge(x, 0) -> true ge(0, s(x)) -> false ge(s(x), s(y)) -> ge(x, y) The set Q consists of the following terms: ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) minus(x0, 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (55) QDPOrderProof (EQUIVALENT) We use the reduction pair processor [LPAR04,JAR06]. The following pairs can be oriented strictly and are deleted. DIV(s(x0), s(s(z1))) -> IFY(true, s(x0), s(s(z1))) IF(true, s(s(x0)), s(s(x1))) -> DIV(minus(x0, x1), s(s(x1))) IFY(true, s(s(y_1)), s(s(x1))) -> IF(ge(y_1, x1), s(s(y_1)), s(s(x1))) The remaining pairs can at least be oriented weakly. Used ordering: Polynomial Order [NEGPOLO,POLO] with Interpretation: POL( DIV_2(x_1, x_2) ) = 2x_1 + 2x_2 + 2 POL( minus_2(x_1, x_2) ) = x_1 + 2 POL( 0 ) = 2 POL( s_1(x_1) ) = 2x_1 + 2 POL( IF_3(x_1, ..., x_3) ) = max{0, 2x_2 + 2x_3 - 2} POL( ge_2(x_1, x_2) ) = 2x_1 POL( true ) = 0 POL( false ) = 1 POL( IFY_3(x_1, ..., x_3) ) = max{0, 2x_1 + 2x_2 + 2x_3 - 1} The following usable rules [FROCOS05] with respect to the argument filtering of the ordering [JAR06] were oriented: minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) ---------------------------------------- (56) Obligation: Q DP problem: P is empty. The TRS R consists of the following rules: minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) ge(x, 0) -> true ge(0, s(x)) -> false ge(s(x), s(y)) -> ge(x, y) The set Q consists of the following terms: ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) minus(x0, 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (57) PisEmptyProof (EQUIVALENT) The TRS P is empty. Hence, there is no (P,Q,R) chain. ---------------------------------------- (58) YES ---------------------------------------- (59) Obligation: Q DP problem: The TRS P consists of the following rules: DIV(s(x0), s(0)) -> IFY(true, s(x0), s(0)) IFY(true, s(z0), s(0)) -> IF(ge(z0, 0), s(z0), s(0)) IF(true, s(x0), s(0)) -> DIV(x0, s(0)) The TRS R consists of the following rules: minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) ge(x, 0) -> true ge(0, s(x)) -> false ge(s(x), s(y)) -> ge(x, y) The set Q consists of the following terms: ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) minus(x0, 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (60) 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. ---------------------------------------- (61) Obligation: Q DP problem: The TRS P consists of the following rules: DIV(s(x0), s(0)) -> IFY(true, s(x0), s(0)) IFY(true, s(z0), s(0)) -> IF(ge(z0, 0), s(z0), s(0)) IF(true, s(x0), s(0)) -> DIV(x0, s(0)) The TRS R consists of the following rules: ge(x, 0) -> true The set Q consists of the following terms: ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) minus(x0, 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (62) 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]. minus(x0, 0) minus(s(x0), s(x1)) ---------------------------------------- (63) Obligation: Q DP problem: The TRS P consists of the following rules: DIV(s(x0), s(0)) -> IFY(true, s(x0), s(0)) IFY(true, s(z0), s(0)) -> IF(ge(z0, 0), s(z0), s(0)) IF(true, s(x0), s(0)) -> DIV(x0, s(0)) The TRS R consists of the following rules: ge(x, 0) -> true The set Q consists of the following terms: ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (64) TransformationProof (EQUIVALENT) By rewriting [LPAR04] the rule IFY(true, s(z0), s(0)) -> IF(ge(z0, 0), s(z0), s(0)) at position [0] we obtained the following new rules [LPAR04]: (IFY(true, s(z0), s(0)) -> IF(true, s(z0), s(0)),IFY(true, s(z0), s(0)) -> IF(true, s(z0), s(0))) ---------------------------------------- (65) Obligation: Q DP problem: The TRS P consists of the following rules: DIV(s(x0), s(0)) -> IFY(true, s(x0), s(0)) IF(true, s(x0), s(0)) -> DIV(x0, s(0)) IFY(true, s(z0), s(0)) -> IF(true, s(z0), s(0)) The TRS R consists of the following rules: ge(x, 0) -> true The set Q consists of the following terms: ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (66) 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. ---------------------------------------- (67) Obligation: Q DP problem: The TRS P consists of the following rules: DIV(s(x0), s(0)) -> IFY(true, s(x0), s(0)) IF(true, s(x0), s(0)) -> DIV(x0, s(0)) IFY(true, s(z0), s(0)) -> IF(true, s(z0), s(0)) R is empty. The set Q consists of the following terms: ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (68) 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]. ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) ---------------------------------------- (69) Obligation: Q DP problem: The TRS P consists of the following rules: DIV(s(x0), s(0)) -> IFY(true, s(x0), s(0)) IF(true, s(x0), s(0)) -> DIV(x0, s(0)) IFY(true, s(z0), s(0)) -> IF(true, s(z0), s(0)) R is empty. Q is empty. We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (70) TransformationProof (EQUIVALENT) By forward instantiating [JAR06] the rule IF(true, s(x0), s(0)) -> DIV(x0, s(0)) we obtained the following new rules [LPAR04]: (IF(true, s(s(y_0)), s(0)) -> DIV(s(y_0), s(0)),IF(true, s(s(y_0)), s(0)) -> DIV(s(y_0), s(0))) ---------------------------------------- (71) Obligation: Q DP problem: The TRS P consists of the following rules: DIV(s(x0), s(0)) -> IFY(true, s(x0), s(0)) IFY(true, s(z0), s(0)) -> IF(true, s(z0), s(0)) IF(true, s(s(y_0)), s(0)) -> DIV(s(y_0), s(0)) R is empty. Q is empty. We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (72) TransformationProof (EQUIVALENT) By forward instantiating [JAR06] the rule IFY(true, s(z0), s(0)) -> IF(true, s(z0), s(0)) we obtained the following new rules [LPAR04]: (IFY(true, s(s(y_0)), s(0)) -> IF(true, s(s(y_0)), s(0)),IFY(true, s(s(y_0)), s(0)) -> IF(true, s(s(y_0)), s(0))) ---------------------------------------- (73) Obligation: Q DP problem: The TRS P consists of the following rules: DIV(s(x0), s(0)) -> IFY(true, s(x0), s(0)) IF(true, s(s(y_0)), s(0)) -> DIV(s(y_0), s(0)) IFY(true, s(s(y_0)), s(0)) -> IF(true, s(s(y_0)), s(0)) R is empty. Q is empty. We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (74) 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: *IFY(true, s(s(y_0)), s(0)) -> IF(true, s(s(y_0)), s(0)) The graph contains the following edges 1 >= 1, 2 >= 2, 3 >= 3 *IF(true, s(s(y_0)), s(0)) -> DIV(s(y_0), s(0)) The graph contains the following edges 2 > 1, 3 >= 2 *DIV(s(x0), s(0)) -> IFY(true, s(x0), s(0)) The graph contains the following edges 1 >= 2, 2 >= 3 ---------------------------------------- (75) YES