YES proof of /export/starexec/sandbox/benchmark/theBenchmark.xml # AProVE Commit ID: 794c25de1cacf0d048858bcd21c9a779e1221865 marcel 20200619 unpublished dirty Termination w.r.t. Q of the given QTRS could be proven: (0) QTRS (1) Overlay + Local Confluence [EQUIVALENT, 15 ms] (2) QTRS (3) DependencyPairsProof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) QDPOrderProof [EQUIVALENT, 8 ms] (34) QDP (35) PisEmptyProof [EQUIVALENT, 0 ms] (36) YES (37) QDP (38) UsableRulesProof [EQUIVALENT, 0 ms] (39) QDP (40) QReductionProof [EQUIVALENT, 0 ms] (41) QDP (42) TransformationProof [EQUIVALENT, 0 ms] (43) QDP (44) DependencyGraphProof [EQUIVALENT, 0 ms] (45) QDP (46) TransformationProof [EQUIVALENT, 0 ms] (47) QDP (48) TransformationProof [EQUIVALENT, 0 ms] (49) QDP (50) TransformationProof [EQUIVALENT, 0 ms] (51) QDP (52) TransformationProof [EQUIVALENT, 0 ms] (53) QDP (54) DependencyGraphProof [EQUIVALENT, 0 ms] (55) QDP (56) UsableRulesProof [EQUIVALENT, 0 ms] (57) QDP (58) TransformationProof [EQUIVALENT, 0 ms] (59) QDP (60) UsableRulesProof [EQUIVALENT, 0 ms] (61) QDP (62) QReductionProof [EQUIVALENT, 0 ms] (63) QDP (64) TransformationProof [EQUIVALENT, 0 ms] (65) QDP (66) TransformationProof [EQUIVALENT, 0 ms] (67) QDP (68) TransformationProof [EQUIVALENT, 0 ms] (69) QDP (70) TransformationProof [EQUIVALENT, 0 ms] (71) QDP (72) TransformationProof [EQUIVALENT, 0 ms] (73) QDP (74) DependencyGraphProof [EQUIVALENT, 0 ms] (75) QDP (76) QDPOrderProof [EQUIVALENT, 0 ms] (77) QDP (78) PisEmptyProof [EQUIVALENT, 0 ms] (79) YES ---------------------------------------- (0) Obligation: Q restricted rewrite system: The TRS R consists of the following rules: minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) quot(0, s(y)) -> 0 quot(s(x), s(y)) -> s(quot(minus(x, y), s(y))) le(0, y) -> true le(s(x), 0) -> false le(s(x), s(y)) -> le(x, y) inc(s(x)) -> s(inc(x)) inc(0) -> s(0) log(x) -> logIter(x, 0) logIter(x, y) -> if(le(s(0), x), le(s(s(0)), x), quot(x, s(s(0))), inc(y)) if(false, b, x, y) -> logZeroError if(true, false, x, s(y)) -> y if(true, true, x, y) -> logIter(x, 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: minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) quot(0, s(y)) -> 0 quot(s(x), s(y)) -> s(quot(minus(x, y), s(y))) le(0, y) -> true le(s(x), 0) -> false le(s(x), s(y)) -> le(x, y) inc(s(x)) -> s(inc(x)) inc(0) -> s(0) log(x) -> logIter(x, 0) logIter(x, y) -> if(le(s(0), x), le(s(s(0)), x), quot(x, s(s(0))), inc(y)) if(false, b, x, y) -> logZeroError if(true, false, x, s(y)) -> y if(true, true, x, y) -> logIter(x, y) The set Q consists of the following terms: minus(x0, 0) minus(s(x0), s(x1)) quot(0, s(x0)) quot(s(x0), s(x1)) le(0, x0) le(s(x0), 0) le(s(x0), s(x1)) inc(s(x0)) inc(0) log(x0) logIter(x0, x1) if(false, x0, x1, x2) if(true, false, x0, s(x1)) if(true, 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: MINUS(s(x), s(y)) -> MINUS(x, y) QUOT(s(x), s(y)) -> QUOT(minus(x, y), s(y)) QUOT(s(x), s(y)) -> MINUS(x, y) LE(s(x), s(y)) -> LE(x, y) INC(s(x)) -> INC(x) LOG(x) -> LOGITER(x, 0) LOGITER(x, y) -> IF(le(s(0), x), le(s(s(0)), x), quot(x, s(s(0))), inc(y)) LOGITER(x, y) -> LE(s(0), x) LOGITER(x, y) -> LE(s(s(0)), x) LOGITER(x, y) -> QUOT(x, s(s(0))) LOGITER(x, y) -> INC(y) IF(true, true, x, y) -> LOGITER(x, y) The TRS R consists of the following rules: minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) quot(0, s(y)) -> 0 quot(s(x), s(y)) -> s(quot(minus(x, y), s(y))) le(0, y) -> true le(s(x), 0) -> false le(s(x), s(y)) -> le(x, y) inc(s(x)) -> s(inc(x)) inc(0) -> s(0) log(x) -> logIter(x, 0) logIter(x, y) -> if(le(s(0), x), le(s(s(0)), x), quot(x, s(s(0))), inc(y)) if(false, b, x, y) -> logZeroError if(true, false, x, s(y)) -> y if(true, true, x, y) -> logIter(x, y) The set Q consists of the following terms: minus(x0, 0) minus(s(x0), s(x1)) quot(0, s(x0)) quot(s(x0), s(x1)) le(0, x0) le(s(x0), 0) le(s(x0), s(x1)) inc(s(x0)) inc(0) log(x0) logIter(x0, x1) if(false, x0, x1, x2) if(true, false, x0, s(x1)) if(true, 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 5 SCCs with 6 less nodes. ---------------------------------------- (6) Complex Obligation (AND) ---------------------------------------- (7) Obligation: Q DP problem: The TRS P consists of the following rules: INC(s(x)) -> INC(x) The TRS R consists of the following rules: minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) quot(0, s(y)) -> 0 quot(s(x), s(y)) -> s(quot(minus(x, y), s(y))) le(0, y) -> true le(s(x), 0) -> false le(s(x), s(y)) -> le(x, y) inc(s(x)) -> s(inc(x)) inc(0) -> s(0) log(x) -> logIter(x, 0) logIter(x, y) -> if(le(s(0), x), le(s(s(0)), x), quot(x, s(s(0))), inc(y)) if(false, b, x, y) -> logZeroError if(true, false, x, s(y)) -> y if(true, true, x, y) -> logIter(x, y) The set Q consists of the following terms: minus(x0, 0) minus(s(x0), s(x1)) quot(0, s(x0)) quot(s(x0), s(x1)) le(0, x0) le(s(x0), 0) le(s(x0), s(x1)) inc(s(x0)) inc(0) log(x0) logIter(x0, x1) if(false, x0, x1, x2) if(true, false, x0, s(x1)) if(true, 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: INC(s(x)) -> INC(x) R is empty. The set Q consists of the following terms: minus(x0, 0) minus(s(x0), s(x1)) quot(0, s(x0)) quot(s(x0), s(x1)) le(0, x0) le(s(x0), 0) le(s(x0), s(x1)) inc(s(x0)) inc(0) log(x0) logIter(x0, x1) if(false, x0, x1, x2) if(true, false, x0, s(x1)) if(true, 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]. minus(x0, 0) minus(s(x0), s(x1)) quot(0, s(x0)) quot(s(x0), s(x1)) le(0, x0) le(s(x0), 0) le(s(x0), s(x1)) inc(s(x0)) inc(0) log(x0) logIter(x0, x1) if(false, x0, x1, x2) if(true, false, x0, s(x1)) if(true, true, x0, x1) ---------------------------------------- (11) Obligation: Q DP problem: The TRS P consists of the following rules: INC(s(x)) -> INC(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: *INC(s(x)) -> INC(x) The graph contains the following edges 1 > 1 ---------------------------------------- (13) YES ---------------------------------------- (14) Obligation: Q DP problem: The TRS P consists of the following rules: LE(s(x), s(y)) -> LE(x, y) The TRS R consists of the following rules: minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) quot(0, s(y)) -> 0 quot(s(x), s(y)) -> s(quot(minus(x, y), s(y))) le(0, y) -> true le(s(x), 0) -> false le(s(x), s(y)) -> le(x, y) inc(s(x)) -> s(inc(x)) inc(0) -> s(0) log(x) -> logIter(x, 0) logIter(x, y) -> if(le(s(0), x), le(s(s(0)), x), quot(x, s(s(0))), inc(y)) if(false, b, x, y) -> logZeroError if(true, false, x, s(y)) -> y if(true, true, x, y) -> logIter(x, y) The set Q consists of the following terms: minus(x0, 0) minus(s(x0), s(x1)) quot(0, s(x0)) quot(s(x0), s(x1)) le(0, x0) le(s(x0), 0) le(s(x0), s(x1)) inc(s(x0)) inc(0) log(x0) logIter(x0, x1) if(false, x0, x1, x2) if(true, false, x0, s(x1)) if(true, 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: LE(s(x), s(y)) -> LE(x, y) R is empty. The set Q consists of the following terms: minus(x0, 0) minus(s(x0), s(x1)) quot(0, s(x0)) quot(s(x0), s(x1)) le(0, x0) le(s(x0), 0) le(s(x0), s(x1)) inc(s(x0)) inc(0) log(x0) logIter(x0, x1) if(false, x0, x1, x2) if(true, false, x0, s(x1)) if(true, 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]. minus(x0, 0) minus(s(x0), s(x1)) quot(0, s(x0)) quot(s(x0), s(x1)) le(0, x0) le(s(x0), 0) le(s(x0), s(x1)) inc(s(x0)) inc(0) log(x0) logIter(x0, x1) if(false, x0, x1, x2) if(true, false, x0, s(x1)) if(true, true, x0, x1) ---------------------------------------- (18) Obligation: Q DP problem: The TRS P consists of the following rules: LE(s(x), s(y)) -> LE(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: *LE(s(x), s(y)) -> LE(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), s(y)) -> MINUS(x, y) The TRS R consists of the following rules: minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) quot(0, s(y)) -> 0 quot(s(x), s(y)) -> s(quot(minus(x, y), s(y))) le(0, y) -> true le(s(x), 0) -> false le(s(x), s(y)) -> le(x, y) inc(s(x)) -> s(inc(x)) inc(0) -> s(0) log(x) -> logIter(x, 0) logIter(x, y) -> if(le(s(0), x), le(s(s(0)), x), quot(x, s(s(0))), inc(y)) if(false, b, x, y) -> logZeroError if(true, false, x, s(y)) -> y if(true, true, x, y) -> logIter(x, y) The set Q consists of the following terms: minus(x0, 0) minus(s(x0), s(x1)) quot(0, s(x0)) quot(s(x0), s(x1)) le(0, x0) le(s(x0), 0) le(s(x0), s(x1)) inc(s(x0)) inc(0) log(x0) logIter(x0, x1) if(false, x0, x1, x2) if(true, false, x0, s(x1)) if(true, 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), s(y)) -> MINUS(x, y) R is empty. The set Q consists of the following terms: minus(x0, 0) minus(s(x0), s(x1)) quot(0, s(x0)) quot(s(x0), s(x1)) le(0, x0) le(s(x0), 0) le(s(x0), s(x1)) inc(s(x0)) inc(0) log(x0) logIter(x0, x1) if(false, x0, x1, x2) if(true, false, x0, s(x1)) if(true, 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]. minus(x0, 0) minus(s(x0), s(x1)) quot(0, s(x0)) quot(s(x0), s(x1)) le(0, x0) le(s(x0), 0) le(s(x0), s(x1)) inc(s(x0)) inc(0) log(x0) logIter(x0, x1) if(false, x0, x1, x2) if(true, false, x0, s(x1)) if(true, true, x0, x1) ---------------------------------------- (25) 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. ---------------------------------------- (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), s(y)) -> MINUS(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: QUOT(s(x), s(y)) -> QUOT(minus(x, y), s(y)) The TRS R consists of the following rules: minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) quot(0, s(y)) -> 0 quot(s(x), s(y)) -> s(quot(minus(x, y), s(y))) le(0, y) -> true le(s(x), 0) -> false le(s(x), s(y)) -> le(x, y) inc(s(x)) -> s(inc(x)) inc(0) -> s(0) log(x) -> logIter(x, 0) logIter(x, y) -> if(le(s(0), x), le(s(s(0)), x), quot(x, s(s(0))), inc(y)) if(false, b, x, y) -> logZeroError if(true, false, x, s(y)) -> y if(true, true, x, y) -> logIter(x, y) The set Q consists of the following terms: minus(x0, 0) minus(s(x0), s(x1)) quot(0, s(x0)) quot(s(x0), s(x1)) le(0, x0) le(s(x0), 0) le(s(x0), s(x1)) inc(s(x0)) inc(0) log(x0) logIter(x0, x1) if(false, x0, x1, x2) if(true, false, x0, s(x1)) if(true, 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: QUOT(s(x), s(y)) -> QUOT(minus(x, y), s(y)) The TRS R consists of the following rules: minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) The set Q consists of the following terms: minus(x0, 0) minus(s(x0), s(x1)) quot(0, s(x0)) quot(s(x0), s(x1)) le(0, x0) le(s(x0), 0) le(s(x0), s(x1)) inc(s(x0)) inc(0) log(x0) logIter(x0, x1) if(false, x0, x1, x2) if(true, false, x0, s(x1)) if(true, 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]. quot(0, s(x0)) quot(s(x0), s(x1)) le(0, x0) le(s(x0), 0) le(s(x0), s(x1)) inc(s(x0)) inc(0) log(x0) logIter(x0, x1) if(false, x0, x1, x2) if(true, false, x0, s(x1)) if(true, true, x0, x1) ---------------------------------------- (32) Obligation: Q DP problem: The TRS P consists of the following rules: QUOT(s(x), s(y)) -> QUOT(minus(x, y), s(y)) The TRS R consists of the following rules: minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) The set Q consists of the following terms: minus(x0, 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (33) QDPOrderProof (EQUIVALENT) We use the reduction pair processor [LPAR04,JAR06]. The following pairs can be oriented strictly and are deleted. QUOT(s(x), s(y)) -> QUOT(minus(x, y), s(y)) The remaining pairs can at least be oriented weakly. Used ordering: Polynomial Order [NEGPOLO,POLO] with Interpretation: POL( QUOT_2(x_1, x_2) ) = max{0, 2x_1 - 2} POL( minus_2(x_1, x_2) ) = x_1 POL( 0 ) = 2 POL( s_1(x_1) ) = 2x_1 + 2 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) ---------------------------------------- (34) 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) The set Q consists of the following terms: minus(x0, 0) minus(s(x0), s(x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (35) PisEmptyProof (EQUIVALENT) The TRS P is empty. Hence, there is no (P,Q,R) chain. ---------------------------------------- (36) YES ---------------------------------------- (37) Obligation: Q DP problem: The TRS P consists of the following rules: LOGITER(x, y) -> IF(le(s(0), x), le(s(s(0)), x), quot(x, s(s(0))), inc(y)) IF(true, true, x, y) -> LOGITER(x, y) The TRS R consists of the following rules: minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) quot(0, s(y)) -> 0 quot(s(x), s(y)) -> s(quot(minus(x, y), s(y))) le(0, y) -> true le(s(x), 0) -> false le(s(x), s(y)) -> le(x, y) inc(s(x)) -> s(inc(x)) inc(0) -> s(0) log(x) -> logIter(x, 0) logIter(x, y) -> if(le(s(0), x), le(s(s(0)), x), quot(x, s(s(0))), inc(y)) if(false, b, x, y) -> logZeroError if(true, false, x, s(y)) -> y if(true, true, x, y) -> logIter(x, y) The set Q consists of the following terms: minus(x0, 0) minus(s(x0), s(x1)) quot(0, s(x0)) quot(s(x0), s(x1)) le(0, x0) le(s(x0), 0) le(s(x0), s(x1)) inc(s(x0)) inc(0) log(x0) logIter(x0, x1) if(false, x0, x1, x2) if(true, false, x0, s(x1)) if(true, true, x0, x1) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (38) 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. ---------------------------------------- (39) Obligation: Q DP problem: The TRS P consists of the following rules: LOGITER(x, y) -> IF(le(s(0), x), le(s(s(0)), x), quot(x, s(s(0))), inc(y)) IF(true, true, x, y) -> LOGITER(x, y) The TRS R consists of the following rules: le(s(x), 0) -> false le(s(x), s(y)) -> le(x, y) quot(0, s(y)) -> 0 quot(s(x), s(y)) -> s(quot(minus(x, y), s(y))) inc(s(x)) -> s(inc(x)) inc(0) -> s(0) minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) le(0, y) -> true The set Q consists of the following terms: minus(x0, 0) minus(s(x0), s(x1)) quot(0, s(x0)) quot(s(x0), s(x1)) le(0, x0) le(s(x0), 0) le(s(x0), s(x1)) inc(s(x0)) inc(0) log(x0) logIter(x0, x1) if(false, x0, x1, x2) if(true, false, x0, s(x1)) if(true, true, x0, x1) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (40) 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]. log(x0) logIter(x0, x1) if(false, x0, x1, x2) if(true, false, x0, s(x1)) if(true, true, x0, x1) ---------------------------------------- (41) Obligation: Q DP problem: The TRS P consists of the following rules: LOGITER(x, y) -> IF(le(s(0), x), le(s(s(0)), x), quot(x, s(s(0))), inc(y)) IF(true, true, x, y) -> LOGITER(x, y) The TRS R consists of the following rules: le(s(x), 0) -> false le(s(x), s(y)) -> le(x, y) quot(0, s(y)) -> 0 quot(s(x), s(y)) -> s(quot(minus(x, y), s(y))) inc(s(x)) -> s(inc(x)) inc(0) -> s(0) minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) le(0, y) -> true The set Q consists of the following terms: minus(x0, 0) minus(s(x0), s(x1)) quot(0, s(x0)) quot(s(x0), s(x1)) le(0, x0) le(s(x0), 0) le(s(x0), s(x1)) inc(s(x0)) inc(0) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (42) TransformationProof (EQUIVALENT) By narrowing [LPAR04] the rule LOGITER(x, y) -> IF(le(s(0), x), le(s(s(0)), x), quot(x, s(s(0))), inc(y)) at position [0] we obtained the following new rules [LPAR04]: (LOGITER(0, y1) -> IF(false, le(s(s(0)), 0), quot(0, s(s(0))), inc(y1)),LOGITER(0, y1) -> IF(false, le(s(s(0)), 0), quot(0, s(s(0))), inc(y1))) (LOGITER(s(x1), y1) -> IF(le(0, x1), le(s(s(0)), s(x1)), quot(s(x1), s(s(0))), inc(y1)),LOGITER(s(x1), y1) -> IF(le(0, x1), le(s(s(0)), s(x1)), quot(s(x1), s(s(0))), inc(y1))) ---------------------------------------- (43) Obligation: Q DP problem: The TRS P consists of the following rules: IF(true, true, x, y) -> LOGITER(x, y) LOGITER(0, y1) -> IF(false, le(s(s(0)), 0), quot(0, s(s(0))), inc(y1)) LOGITER(s(x1), y1) -> IF(le(0, x1), le(s(s(0)), s(x1)), quot(s(x1), s(s(0))), inc(y1)) The TRS R consists of the following rules: le(s(x), 0) -> false le(s(x), s(y)) -> le(x, y) quot(0, s(y)) -> 0 quot(s(x), s(y)) -> s(quot(minus(x, y), s(y))) inc(s(x)) -> s(inc(x)) inc(0) -> s(0) minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) le(0, y) -> true The set Q consists of the following terms: minus(x0, 0) minus(s(x0), s(x1)) quot(0, s(x0)) quot(s(x0), s(x1)) le(0, x0) le(s(x0), 0) le(s(x0), s(x1)) inc(s(x0)) inc(0) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (44) DependencyGraphProof (EQUIVALENT) The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 1 SCC with 1 less node. ---------------------------------------- (45) Obligation: Q DP problem: The TRS P consists of the following rules: LOGITER(s(x1), y1) -> IF(le(0, x1), le(s(s(0)), s(x1)), quot(s(x1), s(s(0))), inc(y1)) IF(true, true, x, y) -> LOGITER(x, y) The TRS R consists of the following rules: le(s(x), 0) -> false le(s(x), s(y)) -> le(x, y) quot(0, s(y)) -> 0 quot(s(x), s(y)) -> s(quot(minus(x, y), s(y))) inc(s(x)) -> s(inc(x)) inc(0) -> s(0) minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) le(0, y) -> true The set Q consists of the following terms: minus(x0, 0) minus(s(x0), s(x1)) quot(0, s(x0)) quot(s(x0), s(x1)) le(0, x0) le(s(x0), 0) le(s(x0), s(x1)) inc(s(x0)) inc(0) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (46) TransformationProof (EQUIVALENT) By rewriting [LPAR04] the rule LOGITER(s(x1), y1) -> IF(le(0, x1), le(s(s(0)), s(x1)), quot(s(x1), s(s(0))), inc(y1)) at position [0] we obtained the following new rules [LPAR04]: (LOGITER(s(x1), y1) -> IF(true, le(s(s(0)), s(x1)), quot(s(x1), s(s(0))), inc(y1)),LOGITER(s(x1), y1) -> IF(true, le(s(s(0)), s(x1)), quot(s(x1), s(s(0))), inc(y1))) ---------------------------------------- (47) Obligation: Q DP problem: The TRS P consists of the following rules: IF(true, true, x, y) -> LOGITER(x, y) LOGITER(s(x1), y1) -> IF(true, le(s(s(0)), s(x1)), quot(s(x1), s(s(0))), inc(y1)) The TRS R consists of the following rules: le(s(x), 0) -> false le(s(x), s(y)) -> le(x, y) quot(0, s(y)) -> 0 quot(s(x), s(y)) -> s(quot(minus(x, y), s(y))) inc(s(x)) -> s(inc(x)) inc(0) -> s(0) minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) le(0, y) -> true The set Q consists of the following terms: minus(x0, 0) minus(s(x0), s(x1)) quot(0, s(x0)) quot(s(x0), s(x1)) le(0, x0) le(s(x0), 0) le(s(x0), s(x1)) inc(s(x0)) inc(0) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (48) TransformationProof (EQUIVALENT) By rewriting [LPAR04] the rule LOGITER(s(x1), y1) -> IF(true, le(s(s(0)), s(x1)), quot(s(x1), s(s(0))), inc(y1)) at position [1] we obtained the following new rules [LPAR04]: (LOGITER(s(x1), y1) -> IF(true, le(s(0), x1), quot(s(x1), s(s(0))), inc(y1)),LOGITER(s(x1), y1) -> IF(true, le(s(0), x1), quot(s(x1), s(s(0))), inc(y1))) ---------------------------------------- (49) Obligation: Q DP problem: The TRS P consists of the following rules: IF(true, true, x, y) -> LOGITER(x, y) LOGITER(s(x1), y1) -> IF(true, le(s(0), x1), quot(s(x1), s(s(0))), inc(y1)) The TRS R consists of the following rules: le(s(x), 0) -> false le(s(x), s(y)) -> le(x, y) quot(0, s(y)) -> 0 quot(s(x), s(y)) -> s(quot(minus(x, y), s(y))) inc(s(x)) -> s(inc(x)) inc(0) -> s(0) minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) le(0, y) -> true The set Q consists of the following terms: minus(x0, 0) minus(s(x0), s(x1)) quot(0, s(x0)) quot(s(x0), s(x1)) le(0, x0) le(s(x0), 0) le(s(x0), s(x1)) inc(s(x0)) inc(0) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (50) TransformationProof (EQUIVALENT) By rewriting [LPAR04] the rule LOGITER(s(x1), y1) -> IF(true, le(s(0), x1), quot(s(x1), s(s(0))), inc(y1)) at position [2] we obtained the following new rules [LPAR04]: (LOGITER(s(x1), y1) -> IF(true, le(s(0), x1), s(quot(minus(x1, s(0)), s(s(0)))), inc(y1)),LOGITER(s(x1), y1) -> IF(true, le(s(0), x1), s(quot(minus(x1, s(0)), s(s(0)))), inc(y1))) ---------------------------------------- (51) Obligation: Q DP problem: The TRS P consists of the following rules: IF(true, true, x, y) -> LOGITER(x, y) LOGITER(s(x1), y1) -> IF(true, le(s(0), x1), s(quot(minus(x1, s(0)), s(s(0)))), inc(y1)) The TRS R consists of the following rules: le(s(x), 0) -> false le(s(x), s(y)) -> le(x, y) quot(0, s(y)) -> 0 quot(s(x), s(y)) -> s(quot(minus(x, y), s(y))) inc(s(x)) -> s(inc(x)) inc(0) -> s(0) minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) le(0, y) -> true The set Q consists of the following terms: minus(x0, 0) minus(s(x0), s(x1)) quot(0, s(x0)) quot(s(x0), s(x1)) le(0, x0) le(s(x0), 0) le(s(x0), s(x1)) inc(s(x0)) inc(0) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (52) TransformationProof (EQUIVALENT) By narrowing [LPAR04] the rule LOGITER(s(x1), y1) -> IF(true, le(s(0), x1), s(quot(minus(x1, s(0)), s(s(0)))), inc(y1)) at position [1] we obtained the following new rules [LPAR04]: (LOGITER(s(0), y1) -> IF(true, false, s(quot(minus(0, s(0)), s(s(0)))), inc(y1)),LOGITER(s(0), y1) -> IF(true, false, s(quot(minus(0, s(0)), s(s(0)))), inc(y1))) (LOGITER(s(s(x1)), y1) -> IF(true, le(0, x1), s(quot(minus(s(x1), s(0)), s(s(0)))), inc(y1)),LOGITER(s(s(x1)), y1) -> IF(true, le(0, x1), s(quot(minus(s(x1), s(0)), s(s(0)))), inc(y1))) ---------------------------------------- (53) Obligation: Q DP problem: The TRS P consists of the following rules: IF(true, true, x, y) -> LOGITER(x, y) LOGITER(s(0), y1) -> IF(true, false, s(quot(minus(0, s(0)), s(s(0)))), inc(y1)) LOGITER(s(s(x1)), y1) -> IF(true, le(0, x1), s(quot(minus(s(x1), s(0)), s(s(0)))), inc(y1)) The TRS R consists of the following rules: le(s(x), 0) -> false le(s(x), s(y)) -> le(x, y) quot(0, s(y)) -> 0 quot(s(x), s(y)) -> s(quot(minus(x, y), s(y))) inc(s(x)) -> s(inc(x)) inc(0) -> s(0) minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) le(0, y) -> true The set Q consists of the following terms: minus(x0, 0) minus(s(x0), s(x1)) quot(0, s(x0)) quot(s(x0), s(x1)) le(0, x0) le(s(x0), 0) le(s(x0), s(x1)) inc(s(x0)) inc(0) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (54) DependencyGraphProof (EQUIVALENT) The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 1 SCC with 1 less node. ---------------------------------------- (55) Obligation: Q DP problem: The TRS P consists of the following rules: LOGITER(s(s(x1)), y1) -> IF(true, le(0, x1), s(quot(minus(s(x1), s(0)), s(s(0)))), inc(y1)) IF(true, true, x, y) -> LOGITER(x, y) The TRS R consists of the following rules: le(s(x), 0) -> false le(s(x), s(y)) -> le(x, y) quot(0, s(y)) -> 0 quot(s(x), s(y)) -> s(quot(minus(x, y), s(y))) inc(s(x)) -> s(inc(x)) inc(0) -> s(0) minus(x, 0) -> x minus(s(x), s(y)) -> minus(x, y) le(0, y) -> true The set Q consists of the following terms: minus(x0, 0) minus(s(x0), s(x1)) quot(0, s(x0)) quot(s(x0), s(x1)) le(0, x0) le(s(x0), 0) le(s(x0), s(x1)) inc(s(x0)) inc(0) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (56) 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. ---------------------------------------- (57) Obligation: Q DP problem: The TRS P consists of the following rules: LOGITER(s(s(x1)), y1) -> IF(true, le(0, x1), s(quot(minus(s(x1), s(0)), s(s(0)))), inc(y1)) IF(true, true, x, y) -> LOGITER(x, y) The TRS R consists of the following rules: le(0, y) -> true minus(s(x), s(y)) -> minus(x, y) quot(0, s(y)) -> 0 quot(s(x), s(y)) -> s(quot(minus(x, y), s(y))) inc(s(x)) -> s(inc(x)) inc(0) -> s(0) minus(x, 0) -> x The set Q consists of the following terms: minus(x0, 0) minus(s(x0), s(x1)) quot(0, s(x0)) quot(s(x0), s(x1)) le(0, x0) le(s(x0), 0) le(s(x0), s(x1)) inc(s(x0)) inc(0) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (58) TransformationProof (EQUIVALENT) By rewriting [LPAR04] the rule LOGITER(s(s(x1)), y1) -> IF(true, le(0, x1), s(quot(minus(s(x1), s(0)), s(s(0)))), inc(y1)) at position [1] we obtained the following new rules [LPAR04]: (LOGITER(s(s(x1)), y1) -> IF(true, true, s(quot(minus(s(x1), s(0)), s(s(0)))), inc(y1)),LOGITER(s(s(x1)), y1) -> IF(true, true, s(quot(minus(s(x1), s(0)), s(s(0)))), inc(y1))) ---------------------------------------- (59) Obligation: Q DP problem: The TRS P consists of the following rules: IF(true, true, x, y) -> LOGITER(x, y) LOGITER(s(s(x1)), y1) -> IF(true, true, s(quot(minus(s(x1), s(0)), s(s(0)))), inc(y1)) The TRS R consists of the following rules: le(0, y) -> true minus(s(x), s(y)) -> minus(x, y) quot(0, s(y)) -> 0 quot(s(x), s(y)) -> s(quot(minus(x, y), s(y))) inc(s(x)) -> s(inc(x)) inc(0) -> s(0) minus(x, 0) -> x The set Q consists of the following terms: minus(x0, 0) minus(s(x0), s(x1)) quot(0, s(x0)) quot(s(x0), s(x1)) le(0, x0) le(s(x0), 0) le(s(x0), s(x1)) inc(s(x0)) inc(0) 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: IF(true, true, x, y) -> LOGITER(x, y) LOGITER(s(s(x1)), y1) -> IF(true, true, s(quot(minus(s(x1), s(0)), s(s(0)))), inc(y1)) The TRS R consists of the following rules: minus(s(x), s(y)) -> minus(x, y) quot(0, s(y)) -> 0 quot(s(x), s(y)) -> s(quot(minus(x, y), s(y))) inc(s(x)) -> s(inc(x)) inc(0) -> s(0) minus(x, 0) -> x The set Q consists of the following terms: minus(x0, 0) minus(s(x0), s(x1)) quot(0, s(x0)) quot(s(x0), s(x1)) le(0, x0) le(s(x0), 0) le(s(x0), s(x1)) inc(s(x0)) inc(0) 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]. le(0, x0) le(s(x0), 0) le(s(x0), s(x1)) ---------------------------------------- (63) Obligation: Q DP problem: The TRS P consists of the following rules: IF(true, true, x, y) -> LOGITER(x, y) LOGITER(s(s(x1)), y1) -> IF(true, true, s(quot(minus(s(x1), s(0)), s(s(0)))), inc(y1)) The TRS R consists of the following rules: minus(s(x), s(y)) -> minus(x, y) quot(0, s(y)) -> 0 quot(s(x), s(y)) -> s(quot(minus(x, y), s(y))) inc(s(x)) -> s(inc(x)) inc(0) -> s(0) minus(x, 0) -> x The set Q consists of the following terms: minus(x0, 0) minus(s(x0), s(x1)) quot(0, s(x0)) quot(s(x0), s(x1)) inc(s(x0)) inc(0) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (64) TransformationProof (EQUIVALENT) By rewriting [LPAR04] the rule LOGITER(s(s(x1)), y1) -> IF(true, true, s(quot(minus(s(x1), s(0)), s(s(0)))), inc(y1)) at position [2,0,0] we obtained the following new rules [LPAR04]: (LOGITER(s(s(x1)), y1) -> IF(true, true, s(quot(minus(x1, 0), s(s(0)))), inc(y1)),LOGITER(s(s(x1)), y1) -> IF(true, true, s(quot(minus(x1, 0), s(s(0)))), inc(y1))) ---------------------------------------- (65) Obligation: Q DP problem: The TRS P consists of the following rules: IF(true, true, x, y) -> LOGITER(x, y) LOGITER(s(s(x1)), y1) -> IF(true, true, s(quot(minus(x1, 0), s(s(0)))), inc(y1)) The TRS R consists of the following rules: minus(s(x), s(y)) -> minus(x, y) quot(0, s(y)) -> 0 quot(s(x), s(y)) -> s(quot(minus(x, y), s(y))) inc(s(x)) -> s(inc(x)) inc(0) -> s(0) minus(x, 0) -> x The set Q consists of the following terms: minus(x0, 0) minus(s(x0), s(x1)) quot(0, s(x0)) quot(s(x0), s(x1)) inc(s(x0)) inc(0) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (66) TransformationProof (EQUIVALENT) By rewriting [LPAR04] the rule LOGITER(s(s(x1)), y1) -> IF(true, true, s(quot(minus(x1, 0), s(s(0)))), inc(y1)) at position [2,0,0] we obtained the following new rules [LPAR04]: (LOGITER(s(s(x1)), y1) -> IF(true, true, s(quot(x1, s(s(0)))), inc(y1)),LOGITER(s(s(x1)), y1) -> IF(true, true, s(quot(x1, s(s(0)))), inc(y1))) ---------------------------------------- (67) Obligation: Q DP problem: The TRS P consists of the following rules: IF(true, true, x, y) -> LOGITER(x, y) LOGITER(s(s(x1)), y1) -> IF(true, true, s(quot(x1, s(s(0)))), inc(y1)) The TRS R consists of the following rules: minus(s(x), s(y)) -> minus(x, y) quot(0, s(y)) -> 0 quot(s(x), s(y)) -> s(quot(minus(x, y), s(y))) inc(s(x)) -> s(inc(x)) inc(0) -> s(0) minus(x, 0) -> x The set Q consists of the following terms: minus(x0, 0) minus(s(x0), s(x1)) quot(0, s(x0)) quot(s(x0), s(x1)) inc(s(x0)) inc(0) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (68) TransformationProof (EQUIVALENT) By instantiating [LPAR04] the rule IF(true, true, x, y) -> LOGITER(x, y) we obtained the following new rules [LPAR04]: (IF(true, true, s(y_0), y_1) -> LOGITER(s(y_0), y_1),IF(true, true, s(y_0), y_1) -> LOGITER(s(y_0), y_1)) ---------------------------------------- (69) Obligation: Q DP problem: The TRS P consists of the following rules: LOGITER(s(s(x1)), y1) -> IF(true, true, s(quot(x1, s(s(0)))), inc(y1)) IF(true, true, s(y_0), y_1) -> LOGITER(s(y_0), y_1) The TRS R consists of the following rules: minus(s(x), s(y)) -> minus(x, y) quot(0, s(y)) -> 0 quot(s(x), s(y)) -> s(quot(minus(x, y), s(y))) inc(s(x)) -> s(inc(x)) inc(0) -> s(0) minus(x, 0) -> x The set Q consists of the following terms: minus(x0, 0) minus(s(x0), s(x1)) quot(0, s(x0)) quot(s(x0), s(x1)) inc(s(x0)) inc(0) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (70) TransformationProof (EQUIVALENT) By forward instantiating [JAR06] the rule IF(true, true, s(y_0), y_1) -> LOGITER(s(y_0), y_1) we obtained the following new rules [LPAR04]: (IF(true, true, s(s(y_0)), x1) -> LOGITER(s(s(y_0)), x1),IF(true, true, s(s(y_0)), x1) -> LOGITER(s(s(y_0)), x1)) ---------------------------------------- (71) Obligation: Q DP problem: The TRS P consists of the following rules: LOGITER(s(s(x1)), y1) -> IF(true, true, s(quot(x1, s(s(0)))), inc(y1)) IF(true, true, s(s(y_0)), x1) -> LOGITER(s(s(y_0)), x1) The TRS R consists of the following rules: minus(s(x), s(y)) -> minus(x, y) quot(0, s(y)) -> 0 quot(s(x), s(y)) -> s(quot(minus(x, y), s(y))) inc(s(x)) -> s(inc(x)) inc(0) -> s(0) minus(x, 0) -> x The set Q consists of the following terms: minus(x0, 0) minus(s(x0), s(x1)) quot(0, s(x0)) quot(s(x0), s(x1)) inc(s(x0)) inc(0) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (72) TransformationProof (EQUIVALENT) By narrowing [LPAR04] the rule LOGITER(s(s(x1)), y1) -> IF(true, true, s(quot(x1, s(s(0)))), inc(y1)) at position [2,0] we obtained the following new rules [LPAR04]: (LOGITER(s(s(0)), y1) -> IF(true, true, s(0), inc(y1)),LOGITER(s(s(0)), y1) -> IF(true, true, s(0), inc(y1))) (LOGITER(s(s(s(x0))), y1) -> IF(true, true, s(s(quot(minus(x0, s(0)), s(s(0))))), inc(y1)),LOGITER(s(s(s(x0))), y1) -> IF(true, true, s(s(quot(minus(x0, s(0)), s(s(0))))), inc(y1))) ---------------------------------------- (73) Obligation: Q DP problem: The TRS P consists of the following rules: IF(true, true, s(s(y_0)), x1) -> LOGITER(s(s(y_0)), x1) LOGITER(s(s(0)), y1) -> IF(true, true, s(0), inc(y1)) LOGITER(s(s(s(x0))), y1) -> IF(true, true, s(s(quot(minus(x0, s(0)), s(s(0))))), inc(y1)) The TRS R consists of the following rules: minus(s(x), s(y)) -> minus(x, y) quot(0, s(y)) -> 0 quot(s(x), s(y)) -> s(quot(minus(x, y), s(y))) inc(s(x)) -> s(inc(x)) inc(0) -> s(0) minus(x, 0) -> x The set Q consists of the following terms: minus(x0, 0) minus(s(x0), s(x1)) quot(0, s(x0)) quot(s(x0), s(x1)) inc(s(x0)) inc(0) 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 1 less node. ---------------------------------------- (75) Obligation: Q DP problem: The TRS P consists of the following rules: LOGITER(s(s(s(x0))), y1) -> IF(true, true, s(s(quot(minus(x0, s(0)), s(s(0))))), inc(y1)) IF(true, true, s(s(y_0)), x1) -> LOGITER(s(s(y_0)), x1) The TRS R consists of the following rules: minus(s(x), s(y)) -> minus(x, y) quot(0, s(y)) -> 0 quot(s(x), s(y)) -> s(quot(minus(x, y), s(y))) inc(s(x)) -> s(inc(x)) inc(0) -> s(0) minus(x, 0) -> x The set Q consists of the following terms: minus(x0, 0) minus(s(x0), s(x1)) quot(0, s(x0)) quot(s(x0), s(x1)) inc(s(x0)) inc(0) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (76) QDPOrderProof (EQUIVALENT) We use the reduction pair processor [LPAR04,JAR06]. The following pairs can be oriented strictly and are deleted. LOGITER(s(s(s(x0))), y1) -> IF(true, true, s(s(quot(minus(x0, s(0)), s(s(0))))), inc(y1)) IF(true, true, s(s(y_0)), x1) -> LOGITER(s(s(y_0)), x1) The remaining pairs can at least be oriented weakly. Used ordering: Polynomial Order [NEGPOLO,POLO] with Interpretation: POL( IF_4(x_1, ..., x_4) ) = max{0, x_2 + 2x_3 - 1} POL( quot_2(x_1, x_2) ) = x_1 POL( s_1(x_1) ) = x_1 + 1 POL( minus_2(x_1, x_2) ) = x_1 POL( 0 ) = 1 POL( inc_1(x_1) ) = 0 POL( LOGITER_2(x_1, x_2) ) = max{0, 2x_1 - 1} POL( true ) = 1 The following usable rules [FROCOS05] with respect to the argument filtering of the ordering [JAR06] were oriented: minus(s(x), s(y)) -> minus(x, y) quot(0, s(y)) -> 0 quot(s(x), s(y)) -> s(quot(minus(x, y), s(y))) minus(x, 0) -> x ---------------------------------------- (77) Obligation: Q DP problem: P is empty. The TRS R consists of the following rules: minus(s(x), s(y)) -> minus(x, y) quot(0, s(y)) -> 0 quot(s(x), s(y)) -> s(quot(minus(x, y), s(y))) inc(s(x)) -> s(inc(x)) inc(0) -> s(0) minus(x, 0) -> x The set Q consists of the following terms: minus(x0, 0) minus(s(x0), s(x1)) quot(0, s(x0)) quot(s(x0), s(x1)) inc(s(x0)) inc(0) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (78) PisEmptyProof (EQUIVALENT) The TRS P is empty. Hence, there is no (P,Q,R) chain. ---------------------------------------- (79) YES