/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# AProVE Commit ID: 48fb2092695e11cc9f56e44b17a92a5f88ffb256 marcel 20180622 unpublished dirty Termination w.r.t. Q of the given QTRS could be proven: (0) QTRS (1) Overlay + Local Confluence [EQUIVALENT, 12 ms] (2) QTRS (3) DependencyPairsProof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) TransformationProof [EQUIVALENT, 0 ms] (41) QDP (42) DependencyGraphProof [EQUIVALENT, 0 ms] (43) QDP (44) TransformationProof [EQUIVALENT, 0 ms] (45) QDP (46) UsableRulesProof [EQUIVALENT, 0 ms] (47) QDP (48) TransformationProof [EQUIVALENT, 0 ms] (49) QDP (50) UsableRulesProof [EQUIVALENT, 0 ms] (51) QDP (52) QReductionProof [EQUIVALENT, 0 ms] (53) QDP (54) TransformationProof [EQUIVALENT, 0 ms] (55) QDP (56) TransformationProof [EQUIVALENT, 0 ms] (57) QDP (58) TransformationProof [EQUIVALENT, 0 ms] (59) QDP (60) UsableRulesProof [EQUIVALENT, 0 ms] (61) QDP (62) TransformationProof [EQUIVALENT, 0 ms] (63) QDP (64) UsableRulesProof [EQUIVALENT, 0 ms] (65) QDP (66) QReductionProof [EQUIVALENT, 0 ms] (67) QDP (68) QDPSizeChangeProof [EQUIVALENT, 0 ms] (69) YES ---------------------------------------- (0) Obligation: Q restricted rewrite system: The TRS R consists of the following rules: +(x, 0) -> x +(x, s(y)) -> s(+(x, y)) *(x, 0) -> 0 *(x, s(y)) -> +(*(x, y), x) ge(x, 0) -> true ge(0, s(y)) -> false ge(s(x), s(y)) -> ge(x, y) -(x, 0) -> x -(s(x), s(y)) -> -(x, y) fact(x) -> iffact(x, ge(x, s(s(0)))) iffact(x, true) -> *(x, fact(-(x, s(0)))) iffact(x, false) -> s(0) Q is empty. ---------------------------------------- (1) Overlay + Local Confluence (EQUIVALENT) The TRS is overlay and locally confluent. By [NOC] we can switch to innermost. ---------------------------------------- (2) Obligation: Q restricted rewrite system: The TRS R consists of the following rules: +(x, 0) -> x +(x, s(y)) -> s(+(x, y)) *(x, 0) -> 0 *(x, s(y)) -> +(*(x, y), x) ge(x, 0) -> true ge(0, s(y)) -> false ge(s(x), s(y)) -> ge(x, y) -(x, 0) -> x -(s(x), s(y)) -> -(x, y) fact(x) -> iffact(x, ge(x, s(s(0)))) iffact(x, true) -> *(x, fact(-(x, s(0)))) iffact(x, false) -> s(0) The set Q consists of the following terms: +(x0, 0) +(x0, s(x1)) *(x0, 0) *(x0, s(x1)) ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) -(x0, 0) -(s(x0), s(x1)) fact(x0) iffact(x0, true) iffact(x0, false) ---------------------------------------- (3) DependencyPairsProof (EQUIVALENT) Using Dependency Pairs [AG00,LPAR04] we result in the following initial DP problem. ---------------------------------------- (4) Obligation: Q DP problem: The TRS P consists of the following rules: +^1(x, s(y)) -> +^1(x, y) *^1(x, s(y)) -> +^1(*(x, y), x) *^1(x, s(y)) -> *^1(x, y) GE(s(x), s(y)) -> GE(x, y) -^1(s(x), s(y)) -> -^1(x, y) FACT(x) -> IFFACT(x, ge(x, s(s(0)))) FACT(x) -> GE(x, s(s(0))) IFFACT(x, true) -> *^1(x, fact(-(x, s(0)))) IFFACT(x, true) -> FACT(-(x, s(0))) IFFACT(x, true) -> -^1(x, s(0)) The TRS R consists of the following rules: +(x, 0) -> x +(x, s(y)) -> s(+(x, y)) *(x, 0) -> 0 *(x, s(y)) -> +(*(x, y), x) ge(x, 0) -> true ge(0, s(y)) -> false ge(s(x), s(y)) -> ge(x, y) -(x, 0) -> x -(s(x), s(y)) -> -(x, y) fact(x) -> iffact(x, ge(x, s(s(0)))) iffact(x, true) -> *(x, fact(-(x, s(0)))) iffact(x, false) -> s(0) The set Q consists of the following terms: +(x0, 0) +(x0, s(x1)) *(x0, 0) *(x0, s(x1)) ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) -(x0, 0) -(s(x0), s(x1)) fact(x0) iffact(x0, true) iffact(x0, false) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (5) DependencyGraphProof (EQUIVALENT) The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 5 SCCs with 4 less nodes. ---------------------------------------- (6) Complex Obligation (AND) ---------------------------------------- (7) Obligation: Q DP problem: The TRS P consists of the following rules: -^1(s(x), s(y)) -> -^1(x, y) The TRS R consists of the following rules: +(x, 0) -> x +(x, s(y)) -> s(+(x, y)) *(x, 0) -> 0 *(x, s(y)) -> +(*(x, y), x) ge(x, 0) -> true ge(0, s(y)) -> false ge(s(x), s(y)) -> ge(x, y) -(x, 0) -> x -(s(x), s(y)) -> -(x, y) fact(x) -> iffact(x, ge(x, s(s(0)))) iffact(x, true) -> *(x, fact(-(x, s(0)))) iffact(x, false) -> s(0) The set Q consists of the following terms: +(x0, 0) +(x0, s(x1)) *(x0, 0) *(x0, s(x1)) ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) -(x0, 0) -(s(x0), s(x1)) fact(x0) iffact(x0, true) iffact(x0, false) 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: -^1(s(x), s(y)) -> -^1(x, y) R is empty. The set Q consists of the following terms: +(x0, 0) +(x0, s(x1)) *(x0, 0) *(x0, s(x1)) ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) -(x0, 0) -(s(x0), s(x1)) fact(x0) iffact(x0, true) iffact(x0, false) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (10) QReductionProof (EQUIVALENT) We deleted the following terms from Q as each root-symbol of these terms does neither occur in P nor in R.[THIEMANN]. +(x0, 0) +(x0, s(x1)) *(x0, 0) *(x0, s(x1)) ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) -(x0, 0) -(s(x0), s(x1)) fact(x0) iffact(x0, true) iffact(x0, false) ---------------------------------------- (11) Obligation: Q DP problem: The TRS P consists of the following rules: -^1(s(x), s(y)) -> -^1(x, y) R is empty. Q is empty. We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (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: *-^1(s(x), s(y)) -> -^1(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: +(x, 0) -> x +(x, s(y)) -> s(+(x, y)) *(x, 0) -> 0 *(x, s(y)) -> +(*(x, y), x) ge(x, 0) -> true ge(0, s(y)) -> false ge(s(x), s(y)) -> ge(x, y) -(x, 0) -> x -(s(x), s(y)) -> -(x, y) fact(x) -> iffact(x, ge(x, s(s(0)))) iffact(x, true) -> *(x, fact(-(x, s(0)))) iffact(x, false) -> s(0) The set Q consists of the following terms: +(x0, 0) +(x0, s(x1)) *(x0, 0) *(x0, s(x1)) ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) -(x0, 0) -(s(x0), s(x1)) fact(x0) iffact(x0, true) iffact(x0, false) 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: +(x0, 0) +(x0, s(x1)) *(x0, 0) *(x0, s(x1)) ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) -(x0, 0) -(s(x0), s(x1)) fact(x0) iffact(x0, true) iffact(x0, false) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (17) QReductionProof (EQUIVALENT) We deleted the following terms from Q as each root-symbol of these terms does neither occur in P nor in R.[THIEMANN]. +(x0, 0) +(x0, s(x1)) *(x0, 0) *(x0, s(x1)) ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) -(x0, 0) -(s(x0), s(x1)) fact(x0) iffact(x0, true) iffact(x0, false) ---------------------------------------- (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: +^1(x, s(y)) -> +^1(x, y) The TRS R consists of the following rules: +(x, 0) -> x +(x, s(y)) -> s(+(x, y)) *(x, 0) -> 0 *(x, s(y)) -> +(*(x, y), x) ge(x, 0) -> true ge(0, s(y)) -> false ge(s(x), s(y)) -> ge(x, y) -(x, 0) -> x -(s(x), s(y)) -> -(x, y) fact(x) -> iffact(x, ge(x, s(s(0)))) iffact(x, true) -> *(x, fact(-(x, s(0)))) iffact(x, false) -> s(0) The set Q consists of the following terms: +(x0, 0) +(x0, s(x1)) *(x0, 0) *(x0, s(x1)) ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) -(x0, 0) -(s(x0), s(x1)) fact(x0) iffact(x0, true) iffact(x0, false) 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: +^1(x, s(y)) -> +^1(x, y) R is empty. The set Q consists of the following terms: +(x0, 0) +(x0, s(x1)) *(x0, 0) *(x0, s(x1)) ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) -(x0, 0) -(s(x0), s(x1)) fact(x0) iffact(x0, true) iffact(x0, false) 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]. +(x0, 0) +(x0, s(x1)) *(x0, 0) *(x0, s(x1)) ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) -(x0, 0) -(s(x0), s(x1)) fact(x0) iffact(x0, true) iffact(x0, false) ---------------------------------------- (25) Obligation: Q DP problem: The TRS P consists of the following rules: +^1(x, s(y)) -> +^1(x, y) 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: *+^1(x, s(y)) -> +^1(x, y) 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: *^1(x, s(y)) -> *^1(x, y) The TRS R consists of the following rules: +(x, 0) -> x +(x, s(y)) -> s(+(x, y)) *(x, 0) -> 0 *(x, s(y)) -> +(*(x, y), x) ge(x, 0) -> true ge(0, s(y)) -> false ge(s(x), s(y)) -> ge(x, y) -(x, 0) -> x -(s(x), s(y)) -> -(x, y) fact(x) -> iffact(x, ge(x, s(s(0)))) iffact(x, true) -> *(x, fact(-(x, s(0)))) iffact(x, false) -> s(0) The set Q consists of the following terms: +(x0, 0) +(x0, s(x1)) *(x0, 0) *(x0, s(x1)) ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) -(x0, 0) -(s(x0), s(x1)) fact(x0) iffact(x0, true) iffact(x0, false) 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: *^1(x, s(y)) -> *^1(x, y) R is empty. The set Q consists of the following terms: +(x0, 0) +(x0, s(x1)) *(x0, 0) *(x0, s(x1)) ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) -(x0, 0) -(s(x0), s(x1)) fact(x0) iffact(x0, true) iffact(x0, false) 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]. +(x0, 0) +(x0, s(x1)) *(x0, 0) *(x0, s(x1)) ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) -(x0, 0) -(s(x0), s(x1)) fact(x0) iffact(x0, true) iffact(x0, false) ---------------------------------------- (32) Obligation: Q DP problem: The TRS P consists of the following rules: *^1(x, s(y)) -> *^1(x, y) 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: **^1(x, s(y)) -> *^1(x, y) 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: IFFACT(x, true) -> FACT(-(x, s(0))) FACT(x) -> IFFACT(x, ge(x, s(s(0)))) The TRS R consists of the following rules: +(x, 0) -> x +(x, s(y)) -> s(+(x, y)) *(x, 0) -> 0 *(x, s(y)) -> +(*(x, y), x) ge(x, 0) -> true ge(0, s(y)) -> false ge(s(x), s(y)) -> ge(x, y) -(x, 0) -> x -(s(x), s(y)) -> -(x, y) fact(x) -> iffact(x, ge(x, s(s(0)))) iffact(x, true) -> *(x, fact(-(x, s(0)))) iffact(x, false) -> s(0) The set Q consists of the following terms: +(x0, 0) +(x0, s(x1)) *(x0, 0) *(x0, s(x1)) ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) -(x0, 0) -(s(x0), s(x1)) fact(x0) iffact(x0, true) iffact(x0, false) 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: IFFACT(x, true) -> FACT(-(x, s(0))) FACT(x) -> IFFACT(x, ge(x, s(s(0)))) The TRS R consists of the following rules: ge(0, s(y)) -> false ge(s(x), s(y)) -> ge(x, y) ge(x, 0) -> true -(s(x), s(y)) -> -(x, y) -(x, 0) -> x The set Q consists of the following terms: +(x0, 0) +(x0, s(x1)) *(x0, 0) *(x0, s(x1)) ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) -(x0, 0) -(s(x0), s(x1)) fact(x0) iffact(x0, true) iffact(x0, false) 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]. +(x0, 0) +(x0, s(x1)) *(x0, 0) *(x0, s(x1)) fact(x0) iffact(x0, true) iffact(x0, false) ---------------------------------------- (39) Obligation: Q DP problem: The TRS P consists of the following rules: IFFACT(x, true) -> FACT(-(x, s(0))) FACT(x) -> IFFACT(x, ge(x, s(s(0)))) The TRS R consists of the following rules: ge(0, s(y)) -> false ge(s(x), s(y)) -> ge(x, y) ge(x, 0) -> true -(s(x), s(y)) -> -(x, y) -(x, 0) -> x The set Q consists of the following terms: ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) -(x0, 0) -(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (40) TransformationProof (EQUIVALENT) By narrowing [LPAR04] the rule FACT(x) -> IFFACT(x, ge(x, s(s(0)))) at position [1] we obtained the following new rules [LPAR04]: (FACT(0) -> IFFACT(0, false),FACT(0) -> IFFACT(0, false)) (FACT(s(x0)) -> IFFACT(s(x0), ge(x0, s(0))),FACT(s(x0)) -> IFFACT(s(x0), ge(x0, s(0)))) ---------------------------------------- (41) Obligation: Q DP problem: The TRS P consists of the following rules: IFFACT(x, true) -> FACT(-(x, s(0))) FACT(0) -> IFFACT(0, false) FACT(s(x0)) -> IFFACT(s(x0), ge(x0, s(0))) The TRS R consists of the following rules: ge(0, s(y)) -> false ge(s(x), s(y)) -> ge(x, y) ge(x, 0) -> true -(s(x), s(y)) -> -(x, y) -(x, 0) -> x The set Q consists of the following terms: ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) -(x0, 0) -(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (42) DependencyGraphProof (EQUIVALENT) The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 1 SCC with 1 less node. ---------------------------------------- (43) Obligation: Q DP problem: The TRS P consists of the following rules: FACT(s(x0)) -> IFFACT(s(x0), ge(x0, s(0))) IFFACT(x, true) -> FACT(-(x, s(0))) The TRS R consists of the following rules: ge(0, s(y)) -> false ge(s(x), s(y)) -> ge(x, y) ge(x, 0) -> true -(s(x), s(y)) -> -(x, y) -(x, 0) -> x The set Q consists of the following terms: ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) -(x0, 0) -(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (44) TransformationProof (EQUIVALENT) By narrowing [LPAR04] the rule IFFACT(x, true) -> FACT(-(x, s(0))) at position [0] we obtained the following new rules [LPAR04]: (IFFACT(s(x0), true) -> FACT(-(x0, 0)),IFFACT(s(x0), true) -> FACT(-(x0, 0))) ---------------------------------------- (45) Obligation: Q DP problem: The TRS P consists of the following rules: FACT(s(x0)) -> IFFACT(s(x0), ge(x0, s(0))) IFFACT(s(x0), true) -> FACT(-(x0, 0)) The TRS R consists of the following rules: ge(0, s(y)) -> false ge(s(x), s(y)) -> ge(x, y) ge(x, 0) -> true -(s(x), s(y)) -> -(x, y) -(x, 0) -> x The set Q consists of the following terms: ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) -(x0, 0) -(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (46) 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. ---------------------------------------- (47) Obligation: Q DP problem: The TRS P consists of the following rules: FACT(s(x0)) -> IFFACT(s(x0), ge(x0, s(0))) IFFACT(s(x0), true) -> FACT(-(x0, 0)) The TRS R consists of the following rules: -(x, 0) -> x ge(0, s(y)) -> false ge(s(x), s(y)) -> ge(x, y) ge(x, 0) -> true The set Q consists of the following terms: ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) -(x0, 0) -(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (48) TransformationProof (EQUIVALENT) By rewriting [LPAR04] the rule IFFACT(s(x0), true) -> FACT(-(x0, 0)) at position [0] we obtained the following new rules [LPAR04]: (IFFACT(s(x0), true) -> FACT(x0),IFFACT(s(x0), true) -> FACT(x0)) ---------------------------------------- (49) Obligation: Q DP problem: The TRS P consists of the following rules: FACT(s(x0)) -> IFFACT(s(x0), ge(x0, s(0))) IFFACT(s(x0), true) -> FACT(x0) The TRS R consists of the following rules: -(x, 0) -> x ge(0, s(y)) -> false ge(s(x), s(y)) -> ge(x, y) ge(x, 0) -> true The set Q consists of the following terms: ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) -(x0, 0) -(s(x0), s(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: FACT(s(x0)) -> IFFACT(s(x0), ge(x0, s(0))) IFFACT(s(x0), true) -> FACT(x0) The TRS R consists of the following rules: ge(0, s(y)) -> false ge(s(x), s(y)) -> ge(x, y) ge(x, 0) -> true The set Q consists of the following terms: ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) -(x0, 0) -(s(x0), s(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]. -(x0, 0) -(s(x0), s(x1)) ---------------------------------------- (53) Obligation: Q DP problem: The TRS P consists of the following rules: FACT(s(x0)) -> IFFACT(s(x0), ge(x0, s(0))) IFFACT(s(x0), true) -> FACT(x0) The TRS R consists of the following rules: ge(0, s(y)) -> false ge(s(x), s(y)) -> ge(x, y) 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. ---------------------------------------- (54) TransformationProof (EQUIVALENT) By forward instantiating [JAR06] the rule IFFACT(s(x0), true) -> FACT(x0) we obtained the following new rules [LPAR04]: (IFFACT(s(s(y_0)), true) -> FACT(s(y_0)),IFFACT(s(s(y_0)), true) -> FACT(s(y_0))) ---------------------------------------- (55) Obligation: Q DP problem: The TRS P consists of the following rules: FACT(s(x0)) -> IFFACT(s(x0), ge(x0, s(0))) IFFACT(s(s(y_0)), true) -> FACT(s(y_0)) The TRS R consists of the following rules: ge(0, s(y)) -> false ge(s(x), s(y)) -> ge(x, y) 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. ---------------------------------------- (56) TransformationProof (EQUIVALENT) By forward instantiating [JAR06] the rule FACT(s(x0)) -> IFFACT(s(x0), ge(x0, s(0))) we obtained the following new rules [LPAR04]: (FACT(s(s(y_0))) -> IFFACT(s(s(y_0)), ge(s(y_0), s(0))),FACT(s(s(y_0))) -> IFFACT(s(s(y_0)), ge(s(y_0), s(0)))) ---------------------------------------- (57) Obligation: Q DP problem: The TRS P consists of the following rules: IFFACT(s(s(y_0)), true) -> FACT(s(y_0)) FACT(s(s(y_0))) -> IFFACT(s(s(y_0)), ge(s(y_0), s(0))) The TRS R consists of the following rules: ge(0, s(y)) -> false ge(s(x), s(y)) -> ge(x, y) 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. ---------------------------------------- (58) TransformationProof (EQUIVALENT) By rewriting [LPAR04] the rule FACT(s(s(y_0))) -> IFFACT(s(s(y_0)), ge(s(y_0), s(0))) at position [1] we obtained the following new rules [LPAR04]: (FACT(s(s(y_0))) -> IFFACT(s(s(y_0)), ge(y_0, 0)),FACT(s(s(y_0))) -> IFFACT(s(s(y_0)), ge(y_0, 0))) ---------------------------------------- (59) Obligation: Q DP problem: The TRS P consists of the following rules: IFFACT(s(s(y_0)), true) -> FACT(s(y_0)) FACT(s(s(y_0))) -> IFFACT(s(s(y_0)), ge(y_0, 0)) The TRS R consists of the following rules: ge(0, s(y)) -> false ge(s(x), s(y)) -> ge(x, y) 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. ---------------------------------------- (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: IFFACT(s(s(y_0)), true) -> FACT(s(y_0)) FACT(s(s(y_0))) -> IFFACT(s(s(y_0)), ge(y_0, 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. ---------------------------------------- (62) TransformationProof (EQUIVALENT) By rewriting [LPAR04] the rule FACT(s(s(y_0))) -> IFFACT(s(s(y_0)), ge(y_0, 0)) at position [1] we obtained the following new rules [LPAR04]: (FACT(s(s(y_0))) -> IFFACT(s(s(y_0)), true),FACT(s(s(y_0))) -> IFFACT(s(s(y_0)), true)) ---------------------------------------- (63) Obligation: Q DP problem: The TRS P consists of the following rules: IFFACT(s(s(y_0)), true) -> FACT(s(y_0)) FACT(s(s(y_0))) -> IFFACT(s(s(y_0)), true) 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) 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: IFFACT(s(s(y_0)), true) -> FACT(s(y_0)) FACT(s(s(y_0))) -> IFFACT(s(s(y_0)), true) 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. ---------------------------------------- (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]. ge(x0, 0) ge(0, s(x0)) ge(s(x0), s(x1)) ---------------------------------------- (67) Obligation: Q DP problem: The TRS P consists of the following rules: IFFACT(s(s(y_0)), true) -> FACT(s(y_0)) FACT(s(s(y_0))) -> IFFACT(s(s(y_0)), true) R is empty. Q is empty. We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (68) 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: *FACT(s(s(y_0))) -> IFFACT(s(s(y_0)), true) The graph contains the following edges 1 >= 1 *IFFACT(s(s(y_0)), true) -> FACT(s(y_0)) The graph contains the following edges 1 > 1 ---------------------------------------- (69) YES