/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# AProVE Commit ID: 48fb2092695e11cc9f56e44b17a92a5f88ffb256 marcel 20180622 unpublished dirty Termination w.r.t. Q of the given QTRS could be proven: (0) QTRS (1) Overlay + Local Confluence [EQUIVALENT, 0 ms] (2) QTRS (3) DependencyPairsProof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, 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) QDPSizeChangeProof [EQUIVALENT, 0 ms] (27) YES (28) QDP (29) UsableRulesProof [EQUIVALENT, 0 ms] (30) QDP (31) QReductionProof [EQUIVALENT, 0 ms] (32) QDP (33) QDPSizeChangeProof [EQUIVALENT, 0 ms] (34) YES (35) QDP (36) UsableRulesProof [EQUIVALENT, 0 ms] (37) QDP (38) QReductionProof [EQUIVALENT, 0 ms] (39) QDP (40) QDPSizeChangeProof [EQUIVALENT, 0 ms] (41) YES (42) QDP (43) UsableRulesProof [EQUIVALENT, 0 ms] (44) QDP (45) QReductionProof [EQUIVALENT, 0 ms] (46) QDP (47) QDPSizeChangeProof [EQUIVALENT, 0 ms] (48) YES (49) QDP (50) UsableRulesProof [EQUIVALENT, 0 ms] (51) QDP (52) QReductionProof [EQUIVALENT, 0 ms] (53) QDP (54) QDPSizeChangeProof [EQUIVALENT, 0 ms] (55) YES (56) QDP (57) UsableRulesProof [EQUIVALENT, 0 ms] (58) QDP (59) QReductionProof [EQUIVALENT, 0 ms] (60) QDP (61) QDPSizeChangeProof [EQUIVALENT, 0 ms] (62) YES (63) QDP (64) UsableRulesProof [EQUIVALENT, 0 ms] (65) QDP (66) QReductionProof [EQUIVALENT, 0 ms] (67) QDP (68) TransformationProof [EQUIVALENT, 0 ms] (69) QDP (70) DependencyGraphProof [EQUIVALENT, 0 ms] (71) QDP (72) TransformationProof [EQUIVALENT, 0 ms] (73) QDP (74) DependencyGraphProof [EQUIVALENT, 0 ms] (75) QDP (76) TransformationProof [EQUIVALENT, 0 ms] (77) QDP (78) TransformationProof [EQUIVALENT, 0 ms] (79) QDP (80) TransformationProof [EQUIVALENT, 0 ms] (81) QDP (82) TransformationProof [EQUIVALENT, 0 ms] (83) QDP (84) DependencyGraphProof [EQUIVALENT, 0 ms] (85) QDP (86) TransformationProof [EQUIVALENT, 0 ms] (87) QDP (88) TransformationProof [EQUIVALENT, 0 ms] (89) QDP (90) TransformationProof [EQUIVALENT, 0 ms] (91) QDP (92) TransformationProof [EQUIVALENT, 0 ms] (93) QDP (94) DependencyGraphProof [EQUIVALENT, 0 ms] (95) AND (96) QDP (97) TransformationProof [EQUIVALENT, 0 ms] (98) QDP (99) TransformationProof [EQUIVALENT, 0 ms] (100) QDP (101) QDPOrderProof [EQUIVALENT, 149 ms] (102) QDP (103) PisEmptyProof [EQUIVALENT, 0 ms] (104) YES (105) QDP (106) UsableRulesProof [EQUIVALENT, 0 ms] (107) QDP (108) TransformationProof [EQUIVALENT, 0 ms] (109) QDP (110) TransformationProof [EQUIVALENT, 0 ms] (111) QDP (112) MRRProof [EQUIVALENT, 0 ms] (113) QDP (114) DependencyGraphProof [EQUIVALENT, 0 ms] (115) TRUE ---------------------------------------- (0) Obligation: Q restricted rewrite system: The TRS R consists of the following rules: ge(0, 0) -> true ge(s(x), 0) -> ge(x, 0) ge(0, s(0)) -> false ge(0, s(s(x))) -> ge(0, s(x)) ge(s(x), s(y)) -> ge(x, y) minus(0, 0) -> 0 minus(0, s(x)) -> minus(0, x) minus(s(x), 0) -> s(minus(x, 0)) minus(s(x), s(y)) -> minus(x, y) plus(0, 0) -> 0 plus(0, s(x)) -> s(plus(0, x)) plus(s(x), y) -> s(plus(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(0, 0) -> true ge(s(x), 0) -> ge(x, 0) ge(0, s(0)) -> false ge(0, s(s(x))) -> ge(0, s(x)) ge(s(x), s(y)) -> ge(x, y) minus(0, 0) -> 0 minus(0, s(x)) -> minus(0, x) minus(s(x), 0) -> s(minus(x, 0)) minus(s(x), s(y)) -> minus(x, y) plus(0, 0) -> 0 plus(0, s(x)) -> s(plus(0, x)) plus(s(x), y) -> s(plus(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(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) plus(0, 0) plus(0, s(x0)) plus(s(x0), 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), 0) -> GE(x, 0) GE(0, s(s(x))) -> GE(0, s(x)) GE(s(x), s(y)) -> GE(x, y) MINUS(0, s(x)) -> MINUS(0, x) MINUS(s(x), 0) -> MINUS(x, 0) MINUS(s(x), s(y)) -> MINUS(x, y) PLUS(0, s(x)) -> PLUS(0, x) PLUS(s(x), y) -> PLUS(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(0, 0) -> true ge(s(x), 0) -> ge(x, 0) ge(0, s(0)) -> false ge(0, s(s(x))) -> ge(0, s(x)) ge(s(x), s(y)) -> ge(x, y) minus(0, 0) -> 0 minus(0, s(x)) -> minus(0, x) minus(s(x), 0) -> s(minus(x, 0)) minus(s(x), s(y)) -> minus(x, y) plus(0, 0) -> 0 plus(0, s(x)) -> s(plus(0, x)) plus(s(x), y) -> s(plus(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(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) plus(0, 0) plus(0, s(x0)) plus(s(x0), 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 9 SCCs with 3 less nodes. ---------------------------------------- (6) Complex Obligation (AND) ---------------------------------------- (7) Obligation: Q DP problem: The TRS P consists of the following rules: PLUS(0, s(x)) -> PLUS(0, x) The TRS R consists of the following rules: ge(0, 0) -> true ge(s(x), 0) -> ge(x, 0) ge(0, s(0)) -> false ge(0, s(s(x))) -> ge(0, s(x)) ge(s(x), s(y)) -> ge(x, y) minus(0, 0) -> 0 minus(0, s(x)) -> minus(0, x) minus(s(x), 0) -> s(minus(x, 0)) minus(s(x), s(y)) -> minus(x, y) plus(0, 0) -> 0 plus(0, s(x)) -> s(plus(0, x)) plus(s(x), y) -> s(plus(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(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) plus(0, 0) plus(0, s(x0)) plus(s(x0), 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: PLUS(0, s(x)) -> PLUS(0, x) R is empty. The set Q consists of the following terms: ge(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) plus(0, 0) plus(0, s(x0)) plus(s(x0), 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(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) plus(0, 0) plus(0, s(x0)) plus(s(x0), 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: PLUS(0, s(x)) -> PLUS(0, x) 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: *PLUS(0, s(x)) -> PLUS(0, x) 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: PLUS(s(x), y) -> PLUS(x, y) The TRS R consists of the following rules: ge(0, 0) -> true ge(s(x), 0) -> ge(x, 0) ge(0, s(0)) -> false ge(0, s(s(x))) -> ge(0, s(x)) ge(s(x), s(y)) -> ge(x, y) minus(0, 0) -> 0 minus(0, s(x)) -> minus(0, x) minus(s(x), 0) -> s(minus(x, 0)) minus(s(x), s(y)) -> minus(x, y) plus(0, 0) -> 0 plus(0, s(x)) -> s(plus(0, x)) plus(s(x), y) -> s(plus(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(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) plus(0, 0) plus(0, s(x0)) plus(s(x0), 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: PLUS(s(x), y) -> PLUS(x, y) R is empty. The set Q consists of the following terms: ge(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) plus(0, 0) plus(0, s(x0)) plus(s(x0), 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(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) plus(0, 0) plus(0, s(x0)) plus(s(x0), 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: PLUS(s(x), y) -> PLUS(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: *PLUS(s(x), y) -> PLUS(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: MINUS(s(x), 0) -> MINUS(x, 0) The TRS R consists of the following rules: ge(0, 0) -> true ge(s(x), 0) -> ge(x, 0) ge(0, s(0)) -> false ge(0, s(s(x))) -> ge(0, s(x)) ge(s(x), s(y)) -> ge(x, y) minus(0, 0) -> 0 minus(0, s(x)) -> minus(0, x) minus(s(x), 0) -> s(minus(x, 0)) minus(s(x), s(y)) -> minus(x, y) plus(0, 0) -> 0 plus(0, s(x)) -> s(plus(0, x)) plus(s(x), y) -> s(plus(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(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) plus(0, 0) plus(0, s(x0)) plus(s(x0), 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: MINUS(s(x), 0) -> MINUS(x, 0) R is empty. The set Q consists of the following terms: ge(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) plus(0, 0) plus(0, s(x0)) plus(s(x0), 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]. ge(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) plus(0, 0) plus(0, s(x0)) plus(s(x0), x1) 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: MINUS(s(x), 0) -> MINUS(x, 0) R is empty. Q is empty. We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (26) 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), 0) -> MINUS(x, 0) The graph contains the following edges 1 > 1, 2 >= 2 ---------------------------------------- (27) YES ---------------------------------------- (28) Obligation: Q DP problem: The TRS P consists of the following rules: MINUS(0, s(x)) -> MINUS(0, x) The TRS R consists of the following rules: ge(0, 0) -> true ge(s(x), 0) -> ge(x, 0) ge(0, s(0)) -> false ge(0, s(s(x))) -> ge(0, s(x)) ge(s(x), s(y)) -> ge(x, y) minus(0, 0) -> 0 minus(0, s(x)) -> minus(0, x) minus(s(x), 0) -> s(minus(x, 0)) minus(s(x), s(y)) -> minus(x, y) plus(0, 0) -> 0 plus(0, s(x)) -> s(plus(0, x)) plus(s(x), y) -> s(plus(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(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) plus(0, 0) plus(0, s(x0)) plus(s(x0), 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. ---------------------------------------- (29) 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. ---------------------------------------- (30) Obligation: Q DP problem: The TRS P consists of the following rules: MINUS(0, s(x)) -> MINUS(0, x) R is empty. The set Q consists of the following terms: ge(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) plus(0, 0) plus(0, s(x0)) plus(s(x0), 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. ---------------------------------------- (31) 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(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) plus(0, 0) plus(0, s(x0)) plus(s(x0), x1) div(x0, x1) ify(false, x0, x1) ify(true, x0, x1) if(false, x0, x1) if(true, x0, x1) ---------------------------------------- (32) Obligation: Q DP problem: The TRS P consists of the following rules: MINUS(0, s(x)) -> MINUS(0, x) R is empty. Q is empty. We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (33) 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(0, s(x)) -> MINUS(0, x) The graph contains the following edges 1 >= 1, 2 > 2 ---------------------------------------- (34) YES ---------------------------------------- (35) 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(0, 0) -> true ge(s(x), 0) -> ge(x, 0) ge(0, s(0)) -> false ge(0, s(s(x))) -> ge(0, s(x)) ge(s(x), s(y)) -> ge(x, y) minus(0, 0) -> 0 minus(0, s(x)) -> minus(0, x) minus(s(x), 0) -> s(minus(x, 0)) minus(s(x), s(y)) -> minus(x, y) plus(0, 0) -> 0 plus(0, s(x)) -> s(plus(0, x)) plus(s(x), y) -> s(plus(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(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) plus(0, 0) plus(0, s(x0)) plus(s(x0), 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. ---------------------------------------- (36) 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. ---------------------------------------- (37) 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(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) plus(0, 0) plus(0, s(x0)) plus(s(x0), 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. ---------------------------------------- (38) 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(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) plus(0, 0) plus(0, s(x0)) plus(s(x0), x1) div(x0, x1) ify(false, x0, x1) ify(true, x0, x1) if(false, x0, x1) if(true, x0, x1) ---------------------------------------- (39) 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. ---------------------------------------- (40) 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 ---------------------------------------- (41) YES ---------------------------------------- (42) Obligation: Q DP problem: The TRS P consists of the following rules: GE(0, s(s(x))) -> GE(0, s(x)) The TRS R consists of the following rules: ge(0, 0) -> true ge(s(x), 0) -> ge(x, 0) ge(0, s(0)) -> false ge(0, s(s(x))) -> ge(0, s(x)) ge(s(x), s(y)) -> ge(x, y) minus(0, 0) -> 0 minus(0, s(x)) -> minus(0, x) minus(s(x), 0) -> s(minus(x, 0)) minus(s(x), s(y)) -> minus(x, y) plus(0, 0) -> 0 plus(0, s(x)) -> s(plus(0, x)) plus(s(x), y) -> s(plus(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(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) plus(0, 0) plus(0, s(x0)) plus(s(x0), 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. ---------------------------------------- (43) 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. ---------------------------------------- (44) Obligation: Q DP problem: The TRS P consists of the following rules: GE(0, s(s(x))) -> GE(0, s(x)) R is empty. The set Q consists of the following terms: ge(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) plus(0, 0) plus(0, s(x0)) plus(s(x0), 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. ---------------------------------------- (45) 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(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) plus(0, 0) plus(0, s(x0)) plus(s(x0), x1) div(x0, x1) ify(false, x0, x1) ify(true, x0, x1) if(false, x0, x1) if(true, x0, x1) ---------------------------------------- (46) Obligation: Q DP problem: The TRS P consists of the following rules: GE(0, s(s(x))) -> GE(0, s(x)) R is empty. Q is empty. We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (47) 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(0, s(s(x))) -> GE(0, s(x)) The graph contains the following edges 1 >= 1, 2 > 2 ---------------------------------------- (48) YES ---------------------------------------- (49) Obligation: Q DP problem: The TRS P consists of the following rules: GE(s(x), 0) -> GE(x, 0) The TRS R consists of the following rules: ge(0, 0) -> true ge(s(x), 0) -> ge(x, 0) ge(0, s(0)) -> false ge(0, s(s(x))) -> ge(0, s(x)) ge(s(x), s(y)) -> ge(x, y) minus(0, 0) -> 0 minus(0, s(x)) -> minus(0, x) minus(s(x), 0) -> s(minus(x, 0)) minus(s(x), s(y)) -> minus(x, y) plus(0, 0) -> 0 plus(0, s(x)) -> s(plus(0, x)) plus(s(x), y) -> s(plus(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(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) plus(0, 0) plus(0, s(x0)) plus(s(x0), 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. ---------------------------------------- (50) 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. ---------------------------------------- (51) Obligation: Q DP problem: The TRS P consists of the following rules: GE(s(x), 0) -> GE(x, 0) R is empty. The set Q consists of the following terms: ge(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) plus(0, 0) plus(0, s(x0)) plus(s(x0), 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. ---------------------------------------- (52) 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(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) plus(0, 0) plus(0, s(x0)) plus(s(x0), x1) div(x0, x1) ify(false, x0, x1) ify(true, x0, x1) if(false, x0, x1) if(true, x0, x1) ---------------------------------------- (53) Obligation: Q DP problem: The TRS P consists of the following rules: GE(s(x), 0) -> GE(x, 0) R is empty. Q is empty. We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (54) 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), 0) -> GE(x, 0) The graph contains the following edges 1 > 1, 2 >= 2 ---------------------------------------- (55) YES ---------------------------------------- (56) 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(0, 0) -> true ge(s(x), 0) -> ge(x, 0) ge(0, s(0)) -> false ge(0, s(s(x))) -> ge(0, s(x)) ge(s(x), s(y)) -> ge(x, y) minus(0, 0) -> 0 minus(0, s(x)) -> minus(0, x) minus(s(x), 0) -> s(minus(x, 0)) minus(s(x), s(y)) -> minus(x, y) plus(0, 0) -> 0 plus(0, s(x)) -> s(plus(0, x)) plus(s(x), y) -> s(plus(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(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) plus(0, 0) plus(0, s(x0)) plus(s(x0), 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. ---------------------------------------- (57) 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. ---------------------------------------- (58) 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(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) plus(0, 0) plus(0, s(x0)) plus(s(x0), 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. ---------------------------------------- (59) 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(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) plus(0, 0) plus(0, s(x0)) plus(s(x0), x1) div(x0, x1) ify(false, x0, x1) ify(true, x0, x1) if(false, x0, x1) if(true, x0, x1) ---------------------------------------- (60) 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. ---------------------------------------- (61) 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 ---------------------------------------- (62) YES ---------------------------------------- (63) 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(0, 0) -> true ge(s(x), 0) -> ge(x, 0) ge(0, s(0)) -> false ge(0, s(s(x))) -> ge(0, s(x)) ge(s(x), s(y)) -> ge(x, y) minus(0, 0) -> 0 minus(0, s(x)) -> minus(0, x) minus(s(x), 0) -> s(minus(x, 0)) minus(s(x), s(y)) -> minus(x, y) plus(0, 0) -> 0 plus(0, s(x)) -> s(plus(0, x)) plus(s(x), y) -> s(plus(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(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) plus(0, 0) plus(0, s(x0)) plus(s(x0), 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. ---------------------------------------- (64) 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. ---------------------------------------- (65) 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(0, 0) -> 0 minus(0, s(x)) -> minus(0, x) minus(s(x), 0) -> s(minus(x, 0)) minus(s(x), s(y)) -> minus(x, y) ge(0, 0) -> true ge(s(x), 0) -> ge(x, 0) ge(0, s(0)) -> false ge(0, s(s(x))) -> ge(0, s(x)) ge(s(x), s(y)) -> ge(x, y) The set Q consists of the following terms: ge(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) plus(0, 0) plus(0, s(x0)) plus(s(x0), 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. ---------------------------------------- (66) 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]. plus(0, 0) plus(0, s(x0)) plus(s(x0), x1) div(x0, x1) ify(false, x0, x1) ify(true, x0, x1) if(false, x0, x1) if(true, x0, x1) ---------------------------------------- (67) 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(0, 0) -> 0 minus(0, s(x)) -> minus(0, x) minus(s(x), 0) -> s(minus(x, 0)) minus(s(x), s(y)) -> minus(x, y) ge(0, 0) -> true ge(s(x), 0) -> ge(x, 0) ge(0, s(0)) -> false ge(0, s(s(x))) -> ge(0, s(x)) ge(s(x), s(y)) -> ge(x, y) The set Q consists of the following terms: ge(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (68) 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))) ---------------------------------------- (69) 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(0, 0) -> 0 minus(0, s(x)) -> minus(0, x) minus(s(x), 0) -> s(minus(x, 0)) minus(s(x), s(y)) -> minus(x, y) ge(0, 0) -> true ge(s(x), 0) -> ge(x, 0) ge(0, s(0)) -> false ge(0, s(s(x))) -> ge(0, s(x)) ge(s(x), s(y)) -> ge(x, y) The set Q consists of the following terms: ge(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (70) DependencyGraphProof (EQUIVALENT) The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 1 SCC with 1 less node. ---------------------------------------- (71) 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(0, 0) -> 0 minus(0, s(x)) -> minus(0, x) minus(s(x), 0) -> s(minus(x, 0)) minus(s(x), s(y)) -> minus(x, y) ge(0, 0) -> true ge(s(x), 0) -> ge(x, 0) ge(0, s(0)) -> false ge(0, s(s(x))) -> ge(0, s(x)) ge(s(x), s(y)) -> ge(x, y) The set Q consists of the following terms: ge(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (72) 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, 0, 0) -> IF(true, 0, 0),IFY(true, 0, 0) -> IF(true, 0, 0)) (IFY(true, s(x0), 0) -> IF(ge(x0, 0), s(x0), 0),IFY(true, s(x0), 0) -> IF(ge(x0, 0), s(x0), 0)) (IFY(true, 0, s(0)) -> IF(false, 0, s(0)),IFY(true, 0, s(0)) -> IF(false, 0, s(0))) (IFY(true, 0, s(s(x0))) -> IF(ge(0, s(x0)), 0, s(s(x0))),IFY(true, 0, s(s(x0))) -> IF(ge(0, s(x0)), 0, s(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))) ---------------------------------------- (73) 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, 0, 0) -> IF(true, 0, 0) IFY(true, s(x0), 0) -> IF(ge(x0, 0), s(x0), 0) IFY(true, 0, s(0)) -> IF(false, 0, s(0)) IFY(true, 0, s(s(x0))) -> IF(ge(0, s(x0)), 0, s(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(0, 0) -> 0 minus(0, s(x)) -> minus(0, x) minus(s(x), 0) -> s(minus(x, 0)) minus(s(x), s(y)) -> minus(x, y) ge(0, 0) -> true ge(s(x), 0) -> ge(x, 0) ge(0, s(0)) -> false ge(0, s(s(x))) -> ge(0, s(x)) ge(s(x), s(y)) -> ge(x, y) The set Q consists of the following terms: ge(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (74) DependencyGraphProof (EQUIVALENT) The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 1 SCC with 4 less nodes. ---------------------------------------- (75) Obligation: Q DP problem: The TRS P consists of the following rules: DIV(y0, s(x0)) -> IFY(ge(x0, 0), 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(0, 0) -> 0 minus(0, s(x)) -> minus(0, x) minus(s(x), 0) -> s(minus(x, 0)) minus(s(x), s(y)) -> minus(x, y) ge(0, 0) -> true ge(s(x), 0) -> ge(x, 0) ge(0, s(0)) -> false ge(0, s(s(x))) -> ge(0, s(x)) ge(s(x), s(y)) -> ge(x, y) The set Q consists of the following terms: ge(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (76) 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))) ---------------------------------------- (77) Obligation: Q DP problem: The TRS P consists of the following rules: DIV(y0, s(x0)) -> IFY(ge(x0, 0), 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(0, 0) -> 0 minus(0, s(x)) -> minus(0, x) minus(s(x), 0) -> s(minus(x, 0)) minus(s(x), s(y)) -> minus(x, y) ge(0, 0) -> true ge(s(x), 0) -> ge(x, 0) ge(0, s(0)) -> false ge(0, s(s(x))) -> ge(0, s(x)) ge(s(x), s(y)) -> ge(x, y) The set Q consists of the following terms: ge(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (78) 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))) ---------------------------------------- (79) Obligation: Q DP problem: The TRS P consists of the following rules: DIV(y0, s(x0)) -> IFY(ge(x0, 0), 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(0, 0) -> 0 minus(0, s(x)) -> minus(0, x) minus(s(x), 0) -> s(minus(x, 0)) minus(s(x), s(y)) -> minus(x, y) ge(0, 0) -> true ge(s(x), 0) -> ge(x, 0) ge(0, s(0)) -> false ge(0, s(s(x))) -> ge(0, s(x)) ge(s(x), s(y)) -> ge(x, y) The set Q consists of the following terms: ge(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (80) TransformationProof (EQUIVALENT) By forward instantiating [JAR06] the rule DIV(y0, s(x0)) -> IFY(ge(x0, 0), y0, s(x0)) we obtained the following new rules [LPAR04]: (DIV(s(y_1), s(x1)) -> IFY(ge(x1, 0), s(y_1), s(x1)),DIV(s(y_1), s(x1)) -> IFY(ge(x1, 0), s(y_1), s(x1))) ---------------------------------------- (81) 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_1), s(x1)) -> IFY(ge(x1, 0), s(y_1), s(x1)) The TRS R consists of the following rules: minus(0, 0) -> 0 minus(0, s(x)) -> minus(0, x) minus(s(x), 0) -> s(minus(x, 0)) minus(s(x), s(y)) -> minus(x, y) ge(0, 0) -> true ge(s(x), 0) -> ge(x, 0) ge(0, s(0)) -> false ge(0, s(s(x))) -> ge(0, s(x)) ge(s(x), s(y)) -> ge(x, y) The set Q consists of the following terms: ge(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (82) 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(0), s(0)) -> DIV(0, s(0)),IF(true, s(0), s(0)) -> DIV(0, s(0))) (IF(true, s(0), s(s(x0))) -> DIV(minus(0, x0), s(s(x0))),IF(true, s(0), s(s(x0))) -> DIV(minus(0, x0), s(s(x0)))) (IF(true, s(s(x0)), s(0)) -> DIV(s(minus(x0, 0)), s(0)),IF(true, s(s(x0)), s(0)) -> DIV(s(minus(x0, 0)), 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)))) ---------------------------------------- (83) 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_1), s(x1)) -> IFY(ge(x1, 0), s(y_1), s(x1)) IF(true, s(0), s(0)) -> DIV(0, s(0)) IF(true, s(0), s(s(x0))) -> DIV(minus(0, x0), s(s(x0))) IF(true, s(s(x0)), s(0)) -> DIV(s(minus(x0, 0)), 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(0, 0) -> 0 minus(0, s(x)) -> minus(0, x) minus(s(x), 0) -> s(minus(x, 0)) minus(s(x), s(y)) -> minus(x, y) ge(0, 0) -> true ge(s(x), 0) -> ge(x, 0) ge(0, s(0)) -> false ge(0, s(s(x))) -> ge(0, s(x)) ge(s(x), s(y)) -> ge(x, y) The set Q consists of the following terms: ge(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (84) DependencyGraphProof (EQUIVALENT) The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 1 SCC with 2 less nodes. ---------------------------------------- (85) Obligation: Q DP problem: The TRS P consists of the following rules: IF(true, s(s(x0)), s(0)) -> DIV(s(minus(x0, 0)), s(0)) DIV(s(y_1), s(x1)) -> IFY(ge(x1, 0), s(y_1), s(x1)) IFY(true, s(x0), s(x1)) -> IF(ge(x0, x1), s(x0), s(x1)) IF(true, s(s(x0)), s(s(x1))) -> DIV(minus(x0, x1), s(s(x1))) The TRS R consists of the following rules: minus(0, 0) -> 0 minus(0, s(x)) -> minus(0, x) minus(s(x), 0) -> s(minus(x, 0)) minus(s(x), s(y)) -> minus(x, y) ge(0, 0) -> true ge(s(x), 0) -> ge(x, 0) ge(0, s(0)) -> false ge(0, s(s(x))) -> ge(0, s(x)) ge(s(x), s(y)) -> ge(x, y) The set Q consists of the following terms: ge(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (86) TransformationProof (EQUIVALENT) By instantiating [LPAR04] the rule DIV(s(y_1), s(x1)) -> IFY(ge(x1, 0), s(y_1), s(x1)) we obtained the following new rules [LPAR04]: (DIV(s(y_0), s(0)) -> IFY(ge(0, 0), s(y_0), s(0)),DIV(s(y_0), s(0)) -> IFY(ge(0, 0), s(y_0), s(0))) (DIV(s(x0), s(s(z1))) -> IFY(ge(s(z1), 0), s(x0), s(s(z1))),DIV(s(x0), s(s(z1))) -> IFY(ge(s(z1), 0), s(x0), s(s(z1)))) ---------------------------------------- (87) Obligation: Q DP problem: The TRS P consists of the following rules: IF(true, s(s(x0)), s(0)) -> DIV(s(minus(x0, 0)), s(0)) IFY(true, s(x0), s(x1)) -> IF(ge(x0, x1), s(x0), s(x1)) IF(true, s(s(x0)), s(s(x1))) -> DIV(minus(x0, x1), s(s(x1))) DIV(s(y_0), s(0)) -> IFY(ge(0, 0), s(y_0), s(0)) DIV(s(x0), s(s(z1))) -> IFY(ge(s(z1), 0), s(x0), s(s(z1))) The TRS R consists of the following rules: minus(0, 0) -> 0 minus(0, s(x)) -> minus(0, x) minus(s(x), 0) -> s(minus(x, 0)) minus(s(x), s(y)) -> minus(x, y) ge(0, 0) -> true ge(s(x), 0) -> ge(x, 0) ge(0, s(0)) -> false ge(0, s(s(x))) -> ge(0, s(x)) ge(s(x), s(y)) -> ge(x, y) The set Q consists of the following terms: ge(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (88) TransformationProof (EQUIVALENT) By rewriting [LPAR04] the rule DIV(s(y_0), s(0)) -> IFY(ge(0, 0), s(y_0), s(0)) at position [0] we obtained the following new rules [LPAR04]: (DIV(s(y_0), s(0)) -> IFY(true, s(y_0), s(0)),DIV(s(y_0), s(0)) -> IFY(true, s(y_0), s(0))) ---------------------------------------- (89) Obligation: Q DP problem: The TRS P consists of the following rules: IF(true, s(s(x0)), s(0)) -> DIV(s(minus(x0, 0)), s(0)) IFY(true, s(x0), s(x1)) -> IF(ge(x0, x1), s(x0), s(x1)) IF(true, s(s(x0)), s(s(x1))) -> DIV(minus(x0, x1), s(s(x1))) DIV(s(x0), s(s(z1))) -> IFY(ge(s(z1), 0), s(x0), s(s(z1))) DIV(s(y_0), s(0)) -> IFY(true, s(y_0), s(0)) The TRS R consists of the following rules: minus(0, 0) -> 0 minus(0, s(x)) -> minus(0, x) minus(s(x), 0) -> s(minus(x, 0)) minus(s(x), s(y)) -> minus(x, y) ge(0, 0) -> true ge(s(x), 0) -> ge(x, 0) ge(0, s(0)) -> false ge(0, s(s(x))) -> ge(0, s(x)) ge(s(x), s(y)) -> ge(x, y) The set Q consists of the following terms: ge(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (90) TransformationProof (EQUIVALENT) By rewriting [LPAR04] the rule DIV(s(x0), s(s(z1))) -> IFY(ge(s(z1), 0), s(x0), s(s(z1))) at position [0] we obtained the following new rules [LPAR04]: (DIV(s(x0), s(s(z1))) -> IFY(ge(z1, 0), s(x0), s(s(z1))),DIV(s(x0), s(s(z1))) -> IFY(ge(z1, 0), s(x0), s(s(z1)))) ---------------------------------------- (91) Obligation: Q DP problem: The TRS P consists of the following rules: IF(true, s(s(x0)), s(0)) -> DIV(s(minus(x0, 0)), s(0)) IFY(true, s(x0), s(x1)) -> IF(ge(x0, x1), s(x0), s(x1)) IF(true, s(s(x0)), s(s(x1))) -> DIV(minus(x0, x1), s(s(x1))) DIV(s(y_0), s(0)) -> IFY(true, s(y_0), s(0)) DIV(s(x0), s(s(z1))) -> IFY(ge(z1, 0), s(x0), s(s(z1))) The TRS R consists of the following rules: minus(0, 0) -> 0 minus(0, s(x)) -> minus(0, x) minus(s(x), 0) -> s(minus(x, 0)) minus(s(x), s(y)) -> minus(x, y) ge(0, 0) -> true ge(s(x), 0) -> ge(x, 0) ge(0, s(0)) -> false ge(0, s(s(x))) -> ge(0, s(x)) ge(s(x), s(y)) -> ge(x, y) The set Q consists of the following terms: ge(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (92) 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)))) ---------------------------------------- (93) Obligation: Q DP problem: The TRS P consists of the following rules: IF(true, s(s(x0)), s(0)) -> DIV(s(minus(x0, 0)), s(0)) IF(true, s(s(x0)), s(s(x1))) -> DIV(minus(x0, x1), s(s(x1))) DIV(s(y_0), s(0)) -> IFY(true, s(y_0), s(0)) DIV(s(x0), s(s(z1))) -> IFY(ge(z1, 0), 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(0, 0) -> 0 minus(0, s(x)) -> minus(0, x) minus(s(x), 0) -> s(minus(x, 0)) minus(s(x), s(y)) -> minus(x, y) ge(0, 0) -> true ge(s(x), 0) -> ge(x, 0) ge(0, s(0)) -> false ge(0, s(s(x))) -> ge(0, s(x)) ge(s(x), s(y)) -> ge(x, y) The set Q consists of the following terms: ge(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (94) DependencyGraphProof (EQUIVALENT) The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 2 SCCs. ---------------------------------------- (95) Complex Obligation (AND) ---------------------------------------- (96) Obligation: Q DP problem: The TRS P consists of the following rules: DIV(s(x0), s(s(z1))) -> IFY(ge(z1, 0), 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(0, 0) -> 0 minus(0, s(x)) -> minus(0, x) minus(s(x), 0) -> s(minus(x, 0)) minus(s(x), s(y)) -> minus(x, y) ge(0, 0) -> true ge(s(x), 0) -> ge(x, 0) ge(0, s(0)) -> false ge(0, s(s(x))) -> ge(0, s(x)) ge(s(x), s(y)) -> ge(x, y) The set Q consists of the following terms: ge(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (97) 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)))) ---------------------------------------- (98) Obligation: Q DP problem: The TRS P consists of the following rules: DIV(s(x0), s(s(z1))) -> IFY(ge(z1, 0), 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(0, 0) -> 0 minus(0, s(x)) -> minus(0, x) minus(s(x), 0) -> s(minus(x, 0)) minus(s(x), s(y)) -> minus(x, y) ge(0, 0) -> true ge(s(x), 0) -> ge(x, 0) ge(0, s(0)) -> false ge(0, s(s(x))) -> ge(0, s(x)) ge(s(x), s(y)) -> ge(x, y) The set Q consists of the following terms: ge(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (99) 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)))) ---------------------------------------- (100) Obligation: Q DP problem: The TRS P consists of the following rules: DIV(s(x0), s(s(z1))) -> IFY(ge(z1, 0), 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(0, 0) -> 0 minus(0, s(x)) -> minus(0, x) minus(s(x), 0) -> s(minus(x, 0)) minus(s(x), s(y)) -> minus(x, y) ge(0, 0) -> true ge(s(x), 0) -> ge(x, 0) ge(0, s(0)) -> false ge(0, s(s(x))) -> ge(0, s(x)) ge(s(x), s(y)) -> ge(x, y) The set Q consists of the following terms: ge(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (101) 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(ge(z1, 0), 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( IF_3(x_1, ..., x_3) ) = max{0, 2x_1 + 2x_2 - 2} POL( IFY_3(x_1, ..., x_3) ) = 2x_2 + 1 POL( ge_2(x_1, x_2) ) = 1 POL( 0 ) = 2 POL( true ) = 0 POL( s_1(x_1) ) = 2x_1 + 2 POL( DIV_2(x_1, x_2) ) = 2x_1 + 2 POL( minus_2(x_1, x_2) ) = max{0, 2x_1 - 2} POL( false ) = 1 The following usable rules [FROCOS05] with respect to the argument filtering of the ordering [JAR06] were oriented: ge(0, 0) -> true ge(s(x), 0) -> ge(x, 0) minus(0, 0) -> 0 minus(0, s(x)) -> minus(0, x) minus(s(x), 0) -> s(minus(x, 0)) minus(s(x), s(y)) -> minus(x, y) ge(0, s(0)) -> false ge(0, s(s(x))) -> ge(0, s(x)) ge(s(x), s(y)) -> ge(x, y) ---------------------------------------- (102) Obligation: Q DP problem: P is empty. The TRS R consists of the following rules: minus(0, 0) -> 0 minus(0, s(x)) -> minus(0, x) minus(s(x), 0) -> s(minus(x, 0)) minus(s(x), s(y)) -> minus(x, y) ge(0, 0) -> true ge(s(x), 0) -> ge(x, 0) ge(0, s(0)) -> false ge(0, s(s(x))) -> ge(0, s(x)) ge(s(x), s(y)) -> ge(x, y) The set Q consists of the following terms: ge(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (103) PisEmptyProof (EQUIVALENT) The TRS P is empty. Hence, there is no (P,Q,R) chain. ---------------------------------------- (104) YES ---------------------------------------- (105) Obligation: Q DP problem: The TRS P consists of the following rules: DIV(s(y_0), s(0)) -> IFY(true, s(y_0), s(0)) IFY(true, s(z0), s(0)) -> IF(ge(z0, 0), s(z0), s(0)) IF(true, s(s(x0)), s(0)) -> DIV(s(minus(x0, 0)), s(0)) The TRS R consists of the following rules: minus(0, 0) -> 0 minus(0, s(x)) -> minus(0, x) minus(s(x), 0) -> s(minus(x, 0)) minus(s(x), s(y)) -> minus(x, y) ge(0, 0) -> true ge(s(x), 0) -> ge(x, 0) ge(0, s(0)) -> false ge(0, s(s(x))) -> ge(0, s(x)) ge(s(x), s(y)) -> ge(x, y) The set Q consists of the following terms: ge(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (106) 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. ---------------------------------------- (107) Obligation: Q DP problem: The TRS P consists of the following rules: DIV(s(y_0), s(0)) -> IFY(true, s(y_0), s(0)) IFY(true, s(z0), s(0)) -> IF(ge(z0, 0), s(z0), s(0)) IF(true, s(s(x0)), s(0)) -> DIV(s(minus(x0, 0)), s(0)) The TRS R consists of the following rules: minus(0, 0) -> 0 minus(s(x), 0) -> s(minus(x, 0)) ge(0, 0) -> true ge(s(x), 0) -> ge(x, 0) The set Q consists of the following terms: ge(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (108) TransformationProof (EQUIVALENT) By forward instantiating [JAR06] the rule IFY(true, s(z0), s(0)) -> IF(ge(z0, 0), s(z0), s(0)) we obtained the following new rules [LPAR04]: (IFY(true, s(s(y_1)), s(0)) -> IF(ge(s(y_1), 0), s(s(y_1)), s(0)),IFY(true, s(s(y_1)), s(0)) -> IF(ge(s(y_1), 0), s(s(y_1)), s(0))) ---------------------------------------- (109) Obligation: Q DP problem: The TRS P consists of the following rules: DIV(s(y_0), s(0)) -> IFY(true, s(y_0), s(0)) IF(true, s(s(x0)), s(0)) -> DIV(s(minus(x0, 0)), s(0)) IFY(true, s(s(y_1)), s(0)) -> IF(ge(s(y_1), 0), s(s(y_1)), s(0)) The TRS R consists of the following rules: minus(0, 0) -> 0 minus(s(x), 0) -> s(minus(x, 0)) ge(0, 0) -> true ge(s(x), 0) -> ge(x, 0) The set Q consists of the following terms: ge(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (110) TransformationProof (EQUIVALENT) By rewriting [LPAR04] the rule IFY(true, s(s(y_1)), s(0)) -> IF(ge(s(y_1), 0), s(s(y_1)), s(0)) at position [0] we obtained the following new rules [LPAR04]: (IFY(true, s(s(y_1)), s(0)) -> IF(ge(y_1, 0), s(s(y_1)), s(0)),IFY(true, s(s(y_1)), s(0)) -> IF(ge(y_1, 0), s(s(y_1)), s(0))) ---------------------------------------- (111) Obligation: Q DP problem: The TRS P consists of the following rules: DIV(s(y_0), s(0)) -> IFY(true, s(y_0), s(0)) IF(true, s(s(x0)), s(0)) -> DIV(s(minus(x0, 0)), s(0)) IFY(true, s(s(y_1)), s(0)) -> IF(ge(y_1, 0), s(s(y_1)), s(0)) The TRS R consists of the following rules: minus(0, 0) -> 0 minus(s(x), 0) -> s(minus(x, 0)) ge(0, 0) -> true ge(s(x), 0) -> ge(x, 0) The set Q consists of the following terms: ge(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (112) MRRProof (EQUIVALENT) By using the rule removal processor [LPAR04] with the following ordering, at least one Dependency Pair or term rewrite system rule of this QDP problem can be strictly oriented. Strictly oriented dependency pairs: IFY(true, s(s(y_1)), s(0)) -> IF(ge(y_1, 0), s(s(y_1)), s(0)) Strictly oriented rules of the TRS R: ge(0, 0) -> true ge(s(x), 0) -> ge(x, 0) Used ordering: Polynomial interpretation [POLO]: POL(0) = 0 POL(DIV(x_1, x_2)) = 1 + 2*x_1 + 2*x_2 POL(IF(x_1, x_2, x_3)) = x_1 + x_2 + 2*x_3 POL(IFY(x_1, x_2, x_3)) = 1 + x_1 + 2*x_2 + 2*x_3 POL(ge(x_1, x_2)) = 1 + 2*x_1 + 2*x_2 POL(minus(x_1, x_2)) = x_1 + x_2 POL(s(x_1)) = 1 + 2*x_1 POL(true) = 0 ---------------------------------------- (113) Obligation: Q DP problem: The TRS P consists of the following rules: DIV(s(y_0), s(0)) -> IFY(true, s(y_0), s(0)) IF(true, s(s(x0)), s(0)) -> DIV(s(minus(x0, 0)), s(0)) The TRS R consists of the following rules: minus(0, 0) -> 0 minus(s(x), 0) -> s(minus(x, 0)) The set Q consists of the following terms: ge(0, 0) ge(s(x0), 0) ge(0, s(0)) ge(0, s(s(x0))) ge(s(x0), s(x1)) minus(0, 0) minus(0, s(x0)) minus(s(x0), 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (114) DependencyGraphProof (EQUIVALENT) The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 0 SCCs with 2 less nodes. ---------------------------------------- (115) TRUE