/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# AProVE Commit ID: 48fb2092695e11cc9f56e44b17a92a5f88ffb256 marcel 20180622 unpublished dirty Termination w.r.t. Q of the given QTRS could be proven: (0) QTRS (1) DependencyPairsProof [EQUIVALENT, 47 ms] (2) QDP (3) DependencyGraphProof [EQUIVALENT, 0 ms] (4) AND (5) QDP (6) UsableRulesProof [EQUIVALENT, 0 ms] (7) QDP (8) QDPSizeChangeProof [EQUIVALENT, 0 ms] (9) YES (10) QDP (11) UsableRulesProof [EQUIVALENT, 0 ms] (12) QDP (13) QDPSizeChangeProof [EQUIVALENT, 0 ms] (14) YES (15) QDP (16) UsableRulesProof [EQUIVALENT, 0 ms] (17) QDP (18) QDPSizeChangeProof [EQUIVALENT, 0 ms] (19) YES (20) QDP (21) UsableRulesProof [EQUIVALENT, 0 ms] (22) QDP (23) QDPSizeChangeProof [EQUIVALENT, 0 ms] (24) YES (25) QDP (26) UsableRulesProof [EQUIVALENT, 0 ms] (27) QDP (28) QDPSizeChangeProof [EQUIVALENT, 0 ms] (29) YES (30) QDP (31) UsableRulesProof [EQUIVALENT, 0 ms] (32) QDP (33) QDPSizeChangeProof [EQUIVALENT, 0 ms] (34) YES (35) QDP (36) QDPOrderProof [EQUIVALENT, 209 ms] (37) QDP (38) QDPOrderProof [EQUIVALENT, 160 ms] (39) QDP (40) QDPOrderProof [EQUIVALENT, 32 ms] (41) QDP (42) QDPOrderProof [EQUIVALENT, 0 ms] (43) QDP (44) DependencyGraphProof [EQUIVALENT, 0 ms] (45) TRUE ---------------------------------------- (0) Obligation: Q restricted rewrite system: The TRS R consists of the following rules: active(eq(0, 0)) -> mark(true) active(eq(s(X), s(Y))) -> mark(eq(X, Y)) active(eq(X, Y)) -> mark(false) active(inf(X)) -> mark(cons(X, inf(s(X)))) active(take(0, X)) -> mark(nil) active(take(s(X), cons(Y, L))) -> mark(cons(Y, take(X, L))) active(length(nil)) -> mark(0) active(length(cons(X, L))) -> mark(s(length(L))) mark(eq(X1, X2)) -> active(eq(X1, X2)) mark(0) -> active(0) mark(true) -> active(true) mark(s(X)) -> active(s(X)) mark(false) -> active(false) mark(inf(X)) -> active(inf(mark(X))) mark(cons(X1, X2)) -> active(cons(X1, X2)) mark(take(X1, X2)) -> active(take(mark(X1), mark(X2))) mark(nil) -> active(nil) mark(length(X)) -> active(length(mark(X))) eq(mark(X1), X2) -> eq(X1, X2) eq(X1, mark(X2)) -> eq(X1, X2) eq(active(X1), X2) -> eq(X1, X2) eq(X1, active(X2)) -> eq(X1, X2) s(mark(X)) -> s(X) s(active(X)) -> s(X) inf(mark(X)) -> inf(X) inf(active(X)) -> inf(X) cons(mark(X1), X2) -> cons(X1, X2) cons(X1, mark(X2)) -> cons(X1, X2) cons(active(X1), X2) -> cons(X1, X2) cons(X1, active(X2)) -> cons(X1, X2) take(mark(X1), X2) -> take(X1, X2) take(X1, mark(X2)) -> take(X1, X2) take(active(X1), X2) -> take(X1, X2) take(X1, active(X2)) -> take(X1, X2) length(mark(X)) -> length(X) length(active(X)) -> length(X) Q is empty. ---------------------------------------- (1) DependencyPairsProof (EQUIVALENT) Using Dependency Pairs [AG00,LPAR04] we result in the following initial DP problem. ---------------------------------------- (2) Obligation: Q DP problem: The TRS P consists of the following rules: ACTIVE(eq(0, 0)) -> MARK(true) ACTIVE(eq(s(X), s(Y))) -> MARK(eq(X, Y)) ACTIVE(eq(s(X), s(Y))) -> EQ(X, Y) ACTIVE(eq(X, Y)) -> MARK(false) ACTIVE(inf(X)) -> MARK(cons(X, inf(s(X)))) ACTIVE(inf(X)) -> CONS(X, inf(s(X))) ACTIVE(inf(X)) -> INF(s(X)) ACTIVE(inf(X)) -> S(X) ACTIVE(take(0, X)) -> MARK(nil) ACTIVE(take(s(X), cons(Y, L))) -> MARK(cons(Y, take(X, L))) ACTIVE(take(s(X), cons(Y, L))) -> CONS(Y, take(X, L)) ACTIVE(take(s(X), cons(Y, L))) -> TAKE(X, L) ACTIVE(length(nil)) -> MARK(0) ACTIVE(length(cons(X, L))) -> MARK(s(length(L))) ACTIVE(length(cons(X, L))) -> S(length(L)) ACTIVE(length(cons(X, L))) -> LENGTH(L) MARK(eq(X1, X2)) -> ACTIVE(eq(X1, X2)) MARK(0) -> ACTIVE(0) MARK(true) -> ACTIVE(true) MARK(s(X)) -> ACTIVE(s(X)) MARK(false) -> ACTIVE(false) MARK(inf(X)) -> ACTIVE(inf(mark(X))) MARK(inf(X)) -> INF(mark(X)) MARK(inf(X)) -> MARK(X) MARK(cons(X1, X2)) -> ACTIVE(cons(X1, X2)) MARK(take(X1, X2)) -> ACTIVE(take(mark(X1), mark(X2))) MARK(take(X1, X2)) -> TAKE(mark(X1), mark(X2)) MARK(take(X1, X2)) -> MARK(X1) MARK(take(X1, X2)) -> MARK(X2) MARK(nil) -> ACTIVE(nil) MARK(length(X)) -> ACTIVE(length(mark(X))) MARK(length(X)) -> LENGTH(mark(X)) MARK(length(X)) -> MARK(X) EQ(mark(X1), X2) -> EQ(X1, X2) EQ(X1, mark(X2)) -> EQ(X1, X2) EQ(active(X1), X2) -> EQ(X1, X2) EQ(X1, active(X2)) -> EQ(X1, X2) S(mark(X)) -> S(X) S(active(X)) -> S(X) INF(mark(X)) -> INF(X) INF(active(X)) -> INF(X) CONS(mark(X1), X2) -> CONS(X1, X2) CONS(X1, mark(X2)) -> CONS(X1, X2) CONS(active(X1), X2) -> CONS(X1, X2) CONS(X1, active(X2)) -> CONS(X1, X2) TAKE(mark(X1), X2) -> TAKE(X1, X2) TAKE(X1, mark(X2)) -> TAKE(X1, X2) TAKE(active(X1), X2) -> TAKE(X1, X2) TAKE(X1, active(X2)) -> TAKE(X1, X2) LENGTH(mark(X)) -> LENGTH(X) LENGTH(active(X)) -> LENGTH(X) The TRS R consists of the following rules: active(eq(0, 0)) -> mark(true) active(eq(s(X), s(Y))) -> mark(eq(X, Y)) active(eq(X, Y)) -> mark(false) active(inf(X)) -> mark(cons(X, inf(s(X)))) active(take(0, X)) -> mark(nil) active(take(s(X), cons(Y, L))) -> mark(cons(Y, take(X, L))) active(length(nil)) -> mark(0) active(length(cons(X, L))) -> mark(s(length(L))) mark(eq(X1, X2)) -> active(eq(X1, X2)) mark(0) -> active(0) mark(true) -> active(true) mark(s(X)) -> active(s(X)) mark(false) -> active(false) mark(inf(X)) -> active(inf(mark(X))) mark(cons(X1, X2)) -> active(cons(X1, X2)) mark(take(X1, X2)) -> active(take(mark(X1), mark(X2))) mark(nil) -> active(nil) mark(length(X)) -> active(length(mark(X))) eq(mark(X1), X2) -> eq(X1, X2) eq(X1, mark(X2)) -> eq(X1, X2) eq(active(X1), X2) -> eq(X1, X2) eq(X1, active(X2)) -> eq(X1, X2) s(mark(X)) -> s(X) s(active(X)) -> s(X) inf(mark(X)) -> inf(X) inf(active(X)) -> inf(X) cons(mark(X1), X2) -> cons(X1, X2) cons(X1, mark(X2)) -> cons(X1, X2) cons(active(X1), X2) -> cons(X1, X2) cons(X1, active(X2)) -> cons(X1, X2) take(mark(X1), X2) -> take(X1, X2) take(X1, mark(X2)) -> take(X1, X2) take(active(X1), X2) -> take(X1, X2) take(X1, active(X2)) -> take(X1, X2) length(mark(X)) -> length(X) length(active(X)) -> length(X) Q is empty. We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (3) DependencyGraphProof (EQUIVALENT) The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 7 SCCs with 19 less nodes. ---------------------------------------- (4) Complex Obligation (AND) ---------------------------------------- (5) Obligation: Q DP problem: The TRS P consists of the following rules: LENGTH(active(X)) -> LENGTH(X) LENGTH(mark(X)) -> LENGTH(X) The TRS R consists of the following rules: active(eq(0, 0)) -> mark(true) active(eq(s(X), s(Y))) -> mark(eq(X, Y)) active(eq(X, Y)) -> mark(false) active(inf(X)) -> mark(cons(X, inf(s(X)))) active(take(0, X)) -> mark(nil) active(take(s(X), cons(Y, L))) -> mark(cons(Y, take(X, L))) active(length(nil)) -> mark(0) active(length(cons(X, L))) -> mark(s(length(L))) mark(eq(X1, X2)) -> active(eq(X1, X2)) mark(0) -> active(0) mark(true) -> active(true) mark(s(X)) -> active(s(X)) mark(false) -> active(false) mark(inf(X)) -> active(inf(mark(X))) mark(cons(X1, X2)) -> active(cons(X1, X2)) mark(take(X1, X2)) -> active(take(mark(X1), mark(X2))) mark(nil) -> active(nil) mark(length(X)) -> active(length(mark(X))) eq(mark(X1), X2) -> eq(X1, X2) eq(X1, mark(X2)) -> eq(X1, X2) eq(active(X1), X2) -> eq(X1, X2) eq(X1, active(X2)) -> eq(X1, X2) s(mark(X)) -> s(X) s(active(X)) -> s(X) inf(mark(X)) -> inf(X) inf(active(X)) -> inf(X) cons(mark(X1), X2) -> cons(X1, X2) cons(X1, mark(X2)) -> cons(X1, X2) cons(active(X1), X2) -> cons(X1, X2) cons(X1, active(X2)) -> cons(X1, X2) take(mark(X1), X2) -> take(X1, X2) take(X1, mark(X2)) -> take(X1, X2) take(active(X1), X2) -> take(X1, X2) take(X1, active(X2)) -> take(X1, X2) length(mark(X)) -> length(X) length(active(X)) -> length(X) Q is empty. We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (6) UsableRulesProof (EQUIVALENT) We can use the usable rules and reduction pair processor [LPAR04] with the Ce-compatible extension of the polynomial order that maps every function symbol to the sum of its arguments. Then, we can delete all non-usable rules [FROCOS05] from R. ---------------------------------------- (7) Obligation: Q DP problem: The TRS P consists of the following rules: LENGTH(active(X)) -> LENGTH(X) LENGTH(mark(X)) -> LENGTH(X) R is empty. Q is empty. We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (8) 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: *LENGTH(active(X)) -> LENGTH(X) The graph contains the following edges 1 > 1 *LENGTH(mark(X)) -> LENGTH(X) The graph contains the following edges 1 > 1 ---------------------------------------- (9) YES ---------------------------------------- (10) Obligation: Q DP problem: The TRS P consists of the following rules: TAKE(X1, mark(X2)) -> TAKE(X1, X2) TAKE(mark(X1), X2) -> TAKE(X1, X2) TAKE(active(X1), X2) -> TAKE(X1, X2) TAKE(X1, active(X2)) -> TAKE(X1, X2) The TRS R consists of the following rules: active(eq(0, 0)) -> mark(true) active(eq(s(X), s(Y))) -> mark(eq(X, Y)) active(eq(X, Y)) -> mark(false) active(inf(X)) -> mark(cons(X, inf(s(X)))) active(take(0, X)) -> mark(nil) active(take(s(X), cons(Y, L))) -> mark(cons(Y, take(X, L))) active(length(nil)) -> mark(0) active(length(cons(X, L))) -> mark(s(length(L))) mark(eq(X1, X2)) -> active(eq(X1, X2)) mark(0) -> active(0) mark(true) -> active(true) mark(s(X)) -> active(s(X)) mark(false) -> active(false) mark(inf(X)) -> active(inf(mark(X))) mark(cons(X1, X2)) -> active(cons(X1, X2)) mark(take(X1, X2)) -> active(take(mark(X1), mark(X2))) mark(nil) -> active(nil) mark(length(X)) -> active(length(mark(X))) eq(mark(X1), X2) -> eq(X1, X2) eq(X1, mark(X2)) -> eq(X1, X2) eq(active(X1), X2) -> eq(X1, X2) eq(X1, active(X2)) -> eq(X1, X2) s(mark(X)) -> s(X) s(active(X)) -> s(X) inf(mark(X)) -> inf(X) inf(active(X)) -> inf(X) cons(mark(X1), X2) -> cons(X1, X2) cons(X1, mark(X2)) -> cons(X1, X2) cons(active(X1), X2) -> cons(X1, X2) cons(X1, active(X2)) -> cons(X1, X2) take(mark(X1), X2) -> take(X1, X2) take(X1, mark(X2)) -> take(X1, X2) take(active(X1), X2) -> take(X1, X2) take(X1, active(X2)) -> take(X1, X2) length(mark(X)) -> length(X) length(active(X)) -> length(X) Q is empty. We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (11) UsableRulesProof (EQUIVALENT) We can use the usable rules and reduction pair processor [LPAR04] with the Ce-compatible extension of the polynomial order that maps every function symbol to the sum of its arguments. Then, we can delete all non-usable rules [FROCOS05] from R. ---------------------------------------- (12) Obligation: Q DP problem: The TRS P consists of the following rules: TAKE(X1, mark(X2)) -> TAKE(X1, X2) TAKE(mark(X1), X2) -> TAKE(X1, X2) TAKE(active(X1), X2) -> TAKE(X1, X2) TAKE(X1, active(X2)) -> TAKE(X1, X2) R is empty. Q is empty. We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (13) 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: *TAKE(X1, mark(X2)) -> TAKE(X1, X2) The graph contains the following edges 1 >= 1, 2 > 2 *TAKE(mark(X1), X2) -> TAKE(X1, X2) The graph contains the following edges 1 > 1, 2 >= 2 *TAKE(active(X1), X2) -> TAKE(X1, X2) The graph contains the following edges 1 > 1, 2 >= 2 *TAKE(X1, active(X2)) -> TAKE(X1, X2) The graph contains the following edges 1 >= 1, 2 > 2 ---------------------------------------- (14) YES ---------------------------------------- (15) Obligation: Q DP problem: The TRS P consists of the following rules: CONS(X1, mark(X2)) -> CONS(X1, X2) CONS(mark(X1), X2) -> CONS(X1, X2) CONS(active(X1), X2) -> CONS(X1, X2) CONS(X1, active(X2)) -> CONS(X1, X2) The TRS R consists of the following rules: active(eq(0, 0)) -> mark(true) active(eq(s(X), s(Y))) -> mark(eq(X, Y)) active(eq(X, Y)) -> mark(false) active(inf(X)) -> mark(cons(X, inf(s(X)))) active(take(0, X)) -> mark(nil) active(take(s(X), cons(Y, L))) -> mark(cons(Y, take(X, L))) active(length(nil)) -> mark(0) active(length(cons(X, L))) -> mark(s(length(L))) mark(eq(X1, X2)) -> active(eq(X1, X2)) mark(0) -> active(0) mark(true) -> active(true) mark(s(X)) -> active(s(X)) mark(false) -> active(false) mark(inf(X)) -> active(inf(mark(X))) mark(cons(X1, X2)) -> active(cons(X1, X2)) mark(take(X1, X2)) -> active(take(mark(X1), mark(X2))) mark(nil) -> active(nil) mark(length(X)) -> active(length(mark(X))) eq(mark(X1), X2) -> eq(X1, X2) eq(X1, mark(X2)) -> eq(X1, X2) eq(active(X1), X2) -> eq(X1, X2) eq(X1, active(X2)) -> eq(X1, X2) s(mark(X)) -> s(X) s(active(X)) -> s(X) inf(mark(X)) -> inf(X) inf(active(X)) -> inf(X) cons(mark(X1), X2) -> cons(X1, X2) cons(X1, mark(X2)) -> cons(X1, X2) cons(active(X1), X2) -> cons(X1, X2) cons(X1, active(X2)) -> cons(X1, X2) take(mark(X1), X2) -> take(X1, X2) take(X1, mark(X2)) -> take(X1, X2) take(active(X1), X2) -> take(X1, X2) take(X1, active(X2)) -> take(X1, X2) length(mark(X)) -> length(X) length(active(X)) -> length(X) Q is empty. We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (16) UsableRulesProof (EQUIVALENT) We can use the usable rules and reduction pair processor [LPAR04] with the Ce-compatible extension of the polynomial order that maps every function symbol to the sum of its arguments. Then, we can delete all non-usable rules [FROCOS05] from R. ---------------------------------------- (17) Obligation: Q DP problem: The TRS P consists of the following rules: CONS(X1, mark(X2)) -> CONS(X1, X2) CONS(mark(X1), X2) -> CONS(X1, X2) CONS(active(X1), X2) -> CONS(X1, X2) CONS(X1, active(X2)) -> CONS(X1, X2) R is empty. Q is empty. We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (18) 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: *CONS(X1, mark(X2)) -> CONS(X1, X2) The graph contains the following edges 1 >= 1, 2 > 2 *CONS(mark(X1), X2) -> CONS(X1, X2) The graph contains the following edges 1 > 1, 2 >= 2 *CONS(active(X1), X2) -> CONS(X1, X2) The graph contains the following edges 1 > 1, 2 >= 2 *CONS(X1, active(X2)) -> CONS(X1, X2) The graph contains the following edges 1 >= 1, 2 > 2 ---------------------------------------- (19) YES ---------------------------------------- (20) Obligation: Q DP problem: The TRS P consists of the following rules: INF(active(X)) -> INF(X) INF(mark(X)) -> INF(X) The TRS R consists of the following rules: active(eq(0, 0)) -> mark(true) active(eq(s(X), s(Y))) -> mark(eq(X, Y)) active(eq(X, Y)) -> mark(false) active(inf(X)) -> mark(cons(X, inf(s(X)))) active(take(0, X)) -> mark(nil) active(take(s(X), cons(Y, L))) -> mark(cons(Y, take(X, L))) active(length(nil)) -> mark(0) active(length(cons(X, L))) -> mark(s(length(L))) mark(eq(X1, X2)) -> active(eq(X1, X2)) mark(0) -> active(0) mark(true) -> active(true) mark(s(X)) -> active(s(X)) mark(false) -> active(false) mark(inf(X)) -> active(inf(mark(X))) mark(cons(X1, X2)) -> active(cons(X1, X2)) mark(take(X1, X2)) -> active(take(mark(X1), mark(X2))) mark(nil) -> active(nil) mark(length(X)) -> active(length(mark(X))) eq(mark(X1), X2) -> eq(X1, X2) eq(X1, mark(X2)) -> eq(X1, X2) eq(active(X1), X2) -> eq(X1, X2) eq(X1, active(X2)) -> eq(X1, X2) s(mark(X)) -> s(X) s(active(X)) -> s(X) inf(mark(X)) -> inf(X) inf(active(X)) -> inf(X) cons(mark(X1), X2) -> cons(X1, X2) cons(X1, mark(X2)) -> cons(X1, X2) cons(active(X1), X2) -> cons(X1, X2) cons(X1, active(X2)) -> cons(X1, X2) take(mark(X1), X2) -> take(X1, X2) take(X1, mark(X2)) -> take(X1, X2) take(active(X1), X2) -> take(X1, X2) take(X1, active(X2)) -> take(X1, X2) length(mark(X)) -> length(X) length(active(X)) -> length(X) Q is empty. We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (21) UsableRulesProof (EQUIVALENT) We can use the usable rules and reduction pair processor [LPAR04] with the Ce-compatible extension of the polynomial order that maps every function symbol to the sum of its arguments. Then, we can delete all non-usable rules [FROCOS05] from R. ---------------------------------------- (22) Obligation: Q DP problem: The TRS P consists of the following rules: INF(active(X)) -> INF(X) INF(mark(X)) -> INF(X) R is empty. Q is empty. We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (23) 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: *INF(active(X)) -> INF(X) The graph contains the following edges 1 > 1 *INF(mark(X)) -> INF(X) The graph contains the following edges 1 > 1 ---------------------------------------- (24) YES ---------------------------------------- (25) Obligation: Q DP problem: The TRS P consists of the following rules: S(active(X)) -> S(X) S(mark(X)) -> S(X) The TRS R consists of the following rules: active(eq(0, 0)) -> mark(true) active(eq(s(X), s(Y))) -> mark(eq(X, Y)) active(eq(X, Y)) -> mark(false) active(inf(X)) -> mark(cons(X, inf(s(X)))) active(take(0, X)) -> mark(nil) active(take(s(X), cons(Y, L))) -> mark(cons(Y, take(X, L))) active(length(nil)) -> mark(0) active(length(cons(X, L))) -> mark(s(length(L))) mark(eq(X1, X2)) -> active(eq(X1, X2)) mark(0) -> active(0) mark(true) -> active(true) mark(s(X)) -> active(s(X)) mark(false) -> active(false) mark(inf(X)) -> active(inf(mark(X))) mark(cons(X1, X2)) -> active(cons(X1, X2)) mark(take(X1, X2)) -> active(take(mark(X1), mark(X2))) mark(nil) -> active(nil) mark(length(X)) -> active(length(mark(X))) eq(mark(X1), X2) -> eq(X1, X2) eq(X1, mark(X2)) -> eq(X1, X2) eq(active(X1), X2) -> eq(X1, X2) eq(X1, active(X2)) -> eq(X1, X2) s(mark(X)) -> s(X) s(active(X)) -> s(X) inf(mark(X)) -> inf(X) inf(active(X)) -> inf(X) cons(mark(X1), X2) -> cons(X1, X2) cons(X1, mark(X2)) -> cons(X1, X2) cons(active(X1), X2) -> cons(X1, X2) cons(X1, active(X2)) -> cons(X1, X2) take(mark(X1), X2) -> take(X1, X2) take(X1, mark(X2)) -> take(X1, X2) take(active(X1), X2) -> take(X1, X2) take(X1, active(X2)) -> take(X1, X2) length(mark(X)) -> length(X) length(active(X)) -> length(X) Q is empty. We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (26) UsableRulesProof (EQUIVALENT) We can use the usable rules and reduction pair processor [LPAR04] with the Ce-compatible extension of the polynomial order that maps every function symbol to the sum of its arguments. Then, we can delete all non-usable rules [FROCOS05] from R. ---------------------------------------- (27) Obligation: Q DP problem: The TRS P consists of the following rules: S(active(X)) -> S(X) S(mark(X)) -> S(X) R is empty. Q is empty. We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (28) 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: *S(active(X)) -> S(X) The graph contains the following edges 1 > 1 *S(mark(X)) -> S(X) The graph contains the following edges 1 > 1 ---------------------------------------- (29) YES ---------------------------------------- (30) Obligation: Q DP problem: The TRS P consists of the following rules: EQ(X1, mark(X2)) -> EQ(X1, X2) EQ(mark(X1), X2) -> EQ(X1, X2) EQ(active(X1), X2) -> EQ(X1, X2) EQ(X1, active(X2)) -> EQ(X1, X2) The TRS R consists of the following rules: active(eq(0, 0)) -> mark(true) active(eq(s(X), s(Y))) -> mark(eq(X, Y)) active(eq(X, Y)) -> mark(false) active(inf(X)) -> mark(cons(X, inf(s(X)))) active(take(0, X)) -> mark(nil) active(take(s(X), cons(Y, L))) -> mark(cons(Y, take(X, L))) active(length(nil)) -> mark(0) active(length(cons(X, L))) -> mark(s(length(L))) mark(eq(X1, X2)) -> active(eq(X1, X2)) mark(0) -> active(0) mark(true) -> active(true) mark(s(X)) -> active(s(X)) mark(false) -> active(false) mark(inf(X)) -> active(inf(mark(X))) mark(cons(X1, X2)) -> active(cons(X1, X2)) mark(take(X1, X2)) -> active(take(mark(X1), mark(X2))) mark(nil) -> active(nil) mark(length(X)) -> active(length(mark(X))) eq(mark(X1), X2) -> eq(X1, X2) eq(X1, mark(X2)) -> eq(X1, X2) eq(active(X1), X2) -> eq(X1, X2) eq(X1, active(X2)) -> eq(X1, X2) s(mark(X)) -> s(X) s(active(X)) -> s(X) inf(mark(X)) -> inf(X) inf(active(X)) -> inf(X) cons(mark(X1), X2) -> cons(X1, X2) cons(X1, mark(X2)) -> cons(X1, X2) cons(active(X1), X2) -> cons(X1, X2) cons(X1, active(X2)) -> cons(X1, X2) take(mark(X1), X2) -> take(X1, X2) take(X1, mark(X2)) -> take(X1, X2) take(active(X1), X2) -> take(X1, X2) take(X1, active(X2)) -> take(X1, X2) length(mark(X)) -> length(X) length(active(X)) -> length(X) Q is empty. We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (31) UsableRulesProof (EQUIVALENT) We can use the usable rules and reduction pair processor [LPAR04] with the Ce-compatible extension of the polynomial order that maps every function symbol to the sum of its arguments. Then, we can delete all non-usable rules [FROCOS05] from R. ---------------------------------------- (32) Obligation: Q DP problem: The TRS P consists of the following rules: EQ(X1, mark(X2)) -> EQ(X1, X2) EQ(mark(X1), X2) -> EQ(X1, X2) EQ(active(X1), X2) -> EQ(X1, X2) EQ(X1, active(X2)) -> EQ(X1, X2) 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: *EQ(X1, mark(X2)) -> EQ(X1, X2) The graph contains the following edges 1 >= 1, 2 > 2 *EQ(mark(X1), X2) -> EQ(X1, X2) The graph contains the following edges 1 > 1, 2 >= 2 *EQ(active(X1), X2) -> EQ(X1, X2) The graph contains the following edges 1 > 1, 2 >= 2 *EQ(X1, active(X2)) -> EQ(X1, X2) 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: ACTIVE(eq(s(X), s(Y))) -> MARK(eq(X, Y)) MARK(eq(X1, X2)) -> ACTIVE(eq(X1, X2)) ACTIVE(inf(X)) -> MARK(cons(X, inf(s(X)))) MARK(s(X)) -> ACTIVE(s(X)) ACTIVE(take(s(X), cons(Y, L))) -> MARK(cons(Y, take(X, L))) MARK(inf(X)) -> ACTIVE(inf(mark(X))) ACTIVE(length(cons(X, L))) -> MARK(s(length(L))) MARK(inf(X)) -> MARK(X) MARK(cons(X1, X2)) -> ACTIVE(cons(X1, X2)) MARK(take(X1, X2)) -> ACTIVE(take(mark(X1), mark(X2))) MARK(take(X1, X2)) -> MARK(X1) MARK(take(X1, X2)) -> MARK(X2) MARK(length(X)) -> ACTIVE(length(mark(X))) MARK(length(X)) -> MARK(X) The TRS R consists of the following rules: active(eq(0, 0)) -> mark(true) active(eq(s(X), s(Y))) -> mark(eq(X, Y)) active(eq(X, Y)) -> mark(false) active(inf(X)) -> mark(cons(X, inf(s(X)))) active(take(0, X)) -> mark(nil) active(take(s(X), cons(Y, L))) -> mark(cons(Y, take(X, L))) active(length(nil)) -> mark(0) active(length(cons(X, L))) -> mark(s(length(L))) mark(eq(X1, X2)) -> active(eq(X1, X2)) mark(0) -> active(0) mark(true) -> active(true) mark(s(X)) -> active(s(X)) mark(false) -> active(false) mark(inf(X)) -> active(inf(mark(X))) mark(cons(X1, X2)) -> active(cons(X1, X2)) mark(take(X1, X2)) -> active(take(mark(X1), mark(X2))) mark(nil) -> active(nil) mark(length(X)) -> active(length(mark(X))) eq(mark(X1), X2) -> eq(X1, X2) eq(X1, mark(X2)) -> eq(X1, X2) eq(active(X1), X2) -> eq(X1, X2) eq(X1, active(X2)) -> eq(X1, X2) s(mark(X)) -> s(X) s(active(X)) -> s(X) inf(mark(X)) -> inf(X) inf(active(X)) -> inf(X) cons(mark(X1), X2) -> cons(X1, X2) cons(X1, mark(X2)) -> cons(X1, X2) cons(active(X1), X2) -> cons(X1, X2) cons(X1, active(X2)) -> cons(X1, X2) take(mark(X1), X2) -> take(X1, X2) take(X1, mark(X2)) -> take(X1, X2) take(active(X1), X2) -> take(X1, X2) take(X1, active(X2)) -> take(X1, X2) length(mark(X)) -> length(X) length(active(X)) -> length(X) Q is empty. We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (36) QDPOrderProof (EQUIVALENT) We use the reduction pair processor [LPAR04,JAR06]. The following pairs can be oriented strictly and are deleted. ACTIVE(take(s(X), cons(Y, L))) -> MARK(cons(Y, take(X, L))) ACTIVE(length(cons(X, L))) -> MARK(s(length(L))) MARK(take(X1, X2)) -> MARK(X1) MARK(take(X1, X2)) -> MARK(X2) MARK(length(X)) -> MARK(X) The remaining pairs can at least be oriented weakly. Used ordering: Combined order from the following AFS and order. ACTIVE(x1) = x1 eq(x1, x2) = eq MARK(x1) = x1 inf(x1) = x1 cons(x1, x2) = cons s(x1) = s take(x1, x2) = take(x1, x2) mark(x1) = x1 length(x1) = length(x1) active(x1) = x1 0 = 0 true = true false = false nil = nil Knuth-Bendix order [KBO] with precedence:trivial and weight map: s=5 true=5 eq=7 length_1=4 take_2=3 0=8 cons=3 false=5 nil=8 The following usable rules [FROCOS05] with respect to the argument filtering of the ordering [JAR06] were oriented: eq(X1, mark(X2)) -> eq(X1, X2) eq(mark(X1), X2) -> eq(X1, X2) eq(active(X1), X2) -> eq(X1, X2) eq(X1, active(X2)) -> eq(X1, X2) s(active(X)) -> s(X) s(mark(X)) -> s(X) inf(active(X)) -> inf(X) inf(mark(X)) -> inf(X) cons(X1, mark(X2)) -> cons(X1, X2) cons(mark(X1), X2) -> cons(X1, X2) cons(active(X1), X2) -> cons(X1, X2) cons(X1, active(X2)) -> cons(X1, X2) take(X1, mark(X2)) -> take(X1, X2) take(mark(X1), X2) -> take(X1, X2) take(active(X1), X2) -> take(X1, X2) take(X1, active(X2)) -> take(X1, X2) active(eq(s(X), s(Y))) -> mark(eq(X, Y)) mark(eq(X1, X2)) -> active(eq(X1, X2)) active(inf(X)) -> mark(cons(X, inf(s(X)))) mark(s(X)) -> active(s(X)) active(take(s(X), cons(Y, L))) -> mark(cons(Y, take(X, L))) mark(inf(X)) -> active(inf(mark(X))) active(length(cons(X, L))) -> mark(s(length(L))) mark(cons(X1, X2)) -> active(cons(X1, X2)) mark(take(X1, X2)) -> active(take(mark(X1), mark(X2))) mark(length(X)) -> active(length(mark(X))) mark(0) -> active(0) mark(true) -> active(true) mark(false) -> active(false) mark(nil) -> active(nil) length(active(X)) -> length(X) length(mark(X)) -> length(X) active(eq(0, 0)) -> mark(true) active(eq(X, Y)) -> mark(false) active(take(0, X)) -> mark(nil) active(length(nil)) -> mark(0) ---------------------------------------- (37) Obligation: Q DP problem: The TRS P consists of the following rules: ACTIVE(eq(s(X), s(Y))) -> MARK(eq(X, Y)) MARK(eq(X1, X2)) -> ACTIVE(eq(X1, X2)) ACTIVE(inf(X)) -> MARK(cons(X, inf(s(X)))) MARK(s(X)) -> ACTIVE(s(X)) MARK(inf(X)) -> ACTIVE(inf(mark(X))) MARK(inf(X)) -> MARK(X) MARK(cons(X1, X2)) -> ACTIVE(cons(X1, X2)) MARK(take(X1, X2)) -> ACTIVE(take(mark(X1), mark(X2))) MARK(length(X)) -> ACTIVE(length(mark(X))) The TRS R consists of the following rules: active(eq(0, 0)) -> mark(true) active(eq(s(X), s(Y))) -> mark(eq(X, Y)) active(eq(X, Y)) -> mark(false) active(inf(X)) -> mark(cons(X, inf(s(X)))) active(take(0, X)) -> mark(nil) active(take(s(X), cons(Y, L))) -> mark(cons(Y, take(X, L))) active(length(nil)) -> mark(0) active(length(cons(X, L))) -> mark(s(length(L))) mark(eq(X1, X2)) -> active(eq(X1, X2)) mark(0) -> active(0) mark(true) -> active(true) mark(s(X)) -> active(s(X)) mark(false) -> active(false) mark(inf(X)) -> active(inf(mark(X))) mark(cons(X1, X2)) -> active(cons(X1, X2)) mark(take(X1, X2)) -> active(take(mark(X1), mark(X2))) mark(nil) -> active(nil) mark(length(X)) -> active(length(mark(X))) eq(mark(X1), X2) -> eq(X1, X2) eq(X1, mark(X2)) -> eq(X1, X2) eq(active(X1), X2) -> eq(X1, X2) eq(X1, active(X2)) -> eq(X1, X2) s(mark(X)) -> s(X) s(active(X)) -> s(X) inf(mark(X)) -> inf(X) inf(active(X)) -> inf(X) cons(mark(X1), X2) -> cons(X1, X2) cons(X1, mark(X2)) -> cons(X1, X2) cons(active(X1), X2) -> cons(X1, X2) cons(X1, active(X2)) -> cons(X1, X2) take(mark(X1), X2) -> take(X1, X2) take(X1, mark(X2)) -> take(X1, X2) take(active(X1), X2) -> take(X1, X2) take(X1, active(X2)) -> take(X1, X2) length(mark(X)) -> length(X) length(active(X)) -> length(X) Q is empty. We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (38) QDPOrderProof (EQUIVALENT) We use the reduction pair processor [LPAR04,JAR06]. The following pairs can be oriented strictly and are deleted. MARK(s(X)) -> ACTIVE(s(X)) MARK(cons(X1, X2)) -> ACTIVE(cons(X1, X2)) MARK(take(X1, X2)) -> ACTIVE(take(mark(X1), mark(X2))) MARK(length(X)) -> ACTIVE(length(mark(X))) The remaining pairs can at least be oriented weakly. Used ordering: Polynomial Order [NEGPOLO,POLO] with Interpretation: POL( ACTIVE_1(x_1) ) = max{0, 2x_1 - 2} POL( MARK_1(x_1) ) = 2 POL( eq_2(x_1, x_2) ) = 2 POL( mark_1(x_1) ) = max{0, -2} POL( active_1(x_1) ) = 1 POL( cons_2(x_1, x_2) ) = 0 POL( inf_1(x_1) ) = 2 POL( s_1(x_1) ) = max{0, -2} POL( length_1(x_1) ) = max{0, -2} POL( take_2(x_1, x_2) ) = max{0, -2} POL( 0 ) = 0 POL( true ) = 0 POL( false ) = 0 POL( nil ) = 0 The following usable rules [FROCOS05] with respect to the argument filtering of the ordering [JAR06] were oriented: eq(X1, mark(X2)) -> eq(X1, X2) eq(mark(X1), X2) -> eq(X1, X2) eq(active(X1), X2) -> eq(X1, X2) eq(X1, active(X2)) -> eq(X1, X2) s(active(X)) -> s(X) s(mark(X)) -> s(X) inf(active(X)) -> inf(X) inf(mark(X)) -> inf(X) cons(X1, mark(X2)) -> cons(X1, X2) cons(mark(X1), X2) -> cons(X1, X2) cons(active(X1), X2) -> cons(X1, X2) cons(X1, active(X2)) -> cons(X1, X2) take(X1, mark(X2)) -> take(X1, X2) take(mark(X1), X2) -> take(X1, X2) take(active(X1), X2) -> take(X1, X2) take(X1, active(X2)) -> take(X1, X2) length(active(X)) -> length(X) length(mark(X)) -> length(X) ---------------------------------------- (39) Obligation: Q DP problem: The TRS P consists of the following rules: ACTIVE(eq(s(X), s(Y))) -> MARK(eq(X, Y)) MARK(eq(X1, X2)) -> ACTIVE(eq(X1, X2)) ACTIVE(inf(X)) -> MARK(cons(X, inf(s(X)))) MARK(inf(X)) -> ACTIVE(inf(mark(X))) MARK(inf(X)) -> MARK(X) The TRS R consists of the following rules: active(eq(0, 0)) -> mark(true) active(eq(s(X), s(Y))) -> mark(eq(X, Y)) active(eq(X, Y)) -> mark(false) active(inf(X)) -> mark(cons(X, inf(s(X)))) active(take(0, X)) -> mark(nil) active(take(s(X), cons(Y, L))) -> mark(cons(Y, take(X, L))) active(length(nil)) -> mark(0) active(length(cons(X, L))) -> mark(s(length(L))) mark(eq(X1, X2)) -> active(eq(X1, X2)) mark(0) -> active(0) mark(true) -> active(true) mark(s(X)) -> active(s(X)) mark(false) -> active(false) mark(inf(X)) -> active(inf(mark(X))) mark(cons(X1, X2)) -> active(cons(X1, X2)) mark(take(X1, X2)) -> active(take(mark(X1), mark(X2))) mark(nil) -> active(nil) mark(length(X)) -> active(length(mark(X))) eq(mark(X1), X2) -> eq(X1, X2) eq(X1, mark(X2)) -> eq(X1, X2) eq(active(X1), X2) -> eq(X1, X2) eq(X1, active(X2)) -> eq(X1, X2) s(mark(X)) -> s(X) s(active(X)) -> s(X) inf(mark(X)) -> inf(X) inf(active(X)) -> inf(X) cons(mark(X1), X2) -> cons(X1, X2) cons(X1, mark(X2)) -> cons(X1, X2) cons(active(X1), X2) -> cons(X1, X2) cons(X1, active(X2)) -> cons(X1, X2) take(mark(X1), X2) -> take(X1, X2) take(X1, mark(X2)) -> take(X1, X2) take(active(X1), X2) -> take(X1, X2) take(X1, active(X2)) -> take(X1, X2) length(mark(X)) -> length(X) length(active(X)) -> length(X) Q is empty. We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (40) QDPOrderProof (EQUIVALENT) We use the reduction pair processor [LPAR04,JAR06]. The following pairs can be oriented strictly and are deleted. ACTIVE(inf(X)) -> MARK(cons(X, inf(s(X)))) MARK(inf(X)) -> MARK(X) The remaining pairs can at least be oriented weakly. Used ordering: Combined order from the following AFS and order. ACTIVE(x1) = x1 eq(x1, x2) = eq MARK(x1) = x1 inf(x1) = inf(x1) cons(x1, x2) = cons mark(x1) = x1 s(x1) = s active(x1) = x1 take(x1, x2) = take length(x1) = length 0 = 0 true = true false = false nil = nil Knuth-Bendix order [KBO] with precedence:trivial and weight map: s=1 true=3 eq=5 length=3 take=5 0=2 inf_1=3 cons=3 false=3 nil=3 The following usable rules [FROCOS05] with respect to the argument filtering of the ordering [JAR06] were oriented: eq(X1, mark(X2)) -> eq(X1, X2) eq(mark(X1), X2) -> eq(X1, X2) eq(active(X1), X2) -> eq(X1, X2) eq(X1, active(X2)) -> eq(X1, X2) s(active(X)) -> s(X) s(mark(X)) -> s(X) inf(active(X)) -> inf(X) inf(mark(X)) -> inf(X) cons(X1, mark(X2)) -> cons(X1, X2) cons(mark(X1), X2) -> cons(X1, X2) cons(active(X1), X2) -> cons(X1, X2) cons(X1, active(X2)) -> cons(X1, X2) active(eq(s(X), s(Y))) -> mark(eq(X, Y)) mark(eq(X1, X2)) -> active(eq(X1, X2)) active(inf(X)) -> mark(cons(X, inf(s(X)))) mark(s(X)) -> active(s(X)) active(take(s(X), cons(Y, L))) -> mark(cons(Y, take(X, L))) mark(inf(X)) -> active(inf(mark(X))) active(length(cons(X, L))) -> mark(s(length(L))) mark(cons(X1, X2)) -> active(cons(X1, X2)) mark(take(X1, X2)) -> active(take(mark(X1), mark(X2))) mark(length(X)) -> active(length(mark(X))) mark(0) -> active(0) mark(true) -> active(true) mark(false) -> active(false) mark(nil) -> active(nil) active(eq(0, 0)) -> mark(true) active(eq(X, Y)) -> mark(false) active(take(0, X)) -> mark(nil) active(length(nil)) -> mark(0) take(X1, mark(X2)) -> take(X1, X2) take(mark(X1), X2) -> take(X1, X2) take(active(X1), X2) -> take(X1, X2) take(X1, active(X2)) -> take(X1, X2) length(active(X)) -> length(X) length(mark(X)) -> length(X) ---------------------------------------- (41) Obligation: Q DP problem: The TRS P consists of the following rules: ACTIVE(eq(s(X), s(Y))) -> MARK(eq(X, Y)) MARK(eq(X1, X2)) -> ACTIVE(eq(X1, X2)) MARK(inf(X)) -> ACTIVE(inf(mark(X))) The TRS R consists of the following rules: active(eq(0, 0)) -> mark(true) active(eq(s(X), s(Y))) -> mark(eq(X, Y)) active(eq(X, Y)) -> mark(false) active(inf(X)) -> mark(cons(X, inf(s(X)))) active(take(0, X)) -> mark(nil) active(take(s(X), cons(Y, L))) -> mark(cons(Y, take(X, L))) active(length(nil)) -> mark(0) active(length(cons(X, L))) -> mark(s(length(L))) mark(eq(X1, X2)) -> active(eq(X1, X2)) mark(0) -> active(0) mark(true) -> active(true) mark(s(X)) -> active(s(X)) mark(false) -> active(false) mark(inf(X)) -> active(inf(mark(X))) mark(cons(X1, X2)) -> active(cons(X1, X2)) mark(take(X1, X2)) -> active(take(mark(X1), mark(X2))) mark(nil) -> active(nil) mark(length(X)) -> active(length(mark(X))) eq(mark(X1), X2) -> eq(X1, X2) eq(X1, mark(X2)) -> eq(X1, X2) eq(active(X1), X2) -> eq(X1, X2) eq(X1, active(X2)) -> eq(X1, X2) s(mark(X)) -> s(X) s(active(X)) -> s(X) inf(mark(X)) -> inf(X) inf(active(X)) -> inf(X) cons(mark(X1), X2) -> cons(X1, X2) cons(X1, mark(X2)) -> cons(X1, X2) cons(active(X1), X2) -> cons(X1, X2) cons(X1, active(X2)) -> cons(X1, X2) take(mark(X1), X2) -> take(X1, X2) take(X1, mark(X2)) -> take(X1, X2) take(active(X1), X2) -> take(X1, X2) take(X1, active(X2)) -> take(X1, X2) length(mark(X)) -> length(X) length(active(X)) -> length(X) Q is empty. We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (42) QDPOrderProof (EQUIVALENT) We use the reduction pair processor [LPAR04,JAR06]. The following pairs can be oriented strictly and are deleted. ACTIVE(eq(s(X), s(Y))) -> MARK(eq(X, Y)) The remaining pairs can at least be oriented weakly. Used ordering: Combined order from the following AFS and order. ACTIVE(x1) = x1 eq(x1, x2) = x2 s(x1) = s(x1) MARK(x1) = x1 inf(x1) = inf mark(x1) = x1 active(x1) = x1 Knuth-Bendix order [KBO] with precedence:trivial and weight map: s_1=1 inf=1 The following usable rules [FROCOS05] with respect to the argument filtering of the ordering [JAR06] were oriented: eq(X1, mark(X2)) -> eq(X1, X2) eq(mark(X1), X2) -> eq(X1, X2) eq(active(X1), X2) -> eq(X1, X2) eq(X1, active(X2)) -> eq(X1, X2) inf(active(X)) -> inf(X) inf(mark(X)) -> inf(X) ---------------------------------------- (43) Obligation: Q DP problem: The TRS P consists of the following rules: MARK(eq(X1, X2)) -> ACTIVE(eq(X1, X2)) MARK(inf(X)) -> ACTIVE(inf(mark(X))) The TRS R consists of the following rules: active(eq(0, 0)) -> mark(true) active(eq(s(X), s(Y))) -> mark(eq(X, Y)) active(eq(X, Y)) -> mark(false) active(inf(X)) -> mark(cons(X, inf(s(X)))) active(take(0, X)) -> mark(nil) active(take(s(X), cons(Y, L))) -> mark(cons(Y, take(X, L))) active(length(nil)) -> mark(0) active(length(cons(X, L))) -> mark(s(length(L))) mark(eq(X1, X2)) -> active(eq(X1, X2)) mark(0) -> active(0) mark(true) -> active(true) mark(s(X)) -> active(s(X)) mark(false) -> active(false) mark(inf(X)) -> active(inf(mark(X))) mark(cons(X1, X2)) -> active(cons(X1, X2)) mark(take(X1, X2)) -> active(take(mark(X1), mark(X2))) mark(nil) -> active(nil) mark(length(X)) -> active(length(mark(X))) eq(mark(X1), X2) -> eq(X1, X2) eq(X1, mark(X2)) -> eq(X1, X2) eq(active(X1), X2) -> eq(X1, X2) eq(X1, active(X2)) -> eq(X1, X2) s(mark(X)) -> s(X) s(active(X)) -> s(X) inf(mark(X)) -> inf(X) inf(active(X)) -> inf(X) cons(mark(X1), X2) -> cons(X1, X2) cons(X1, mark(X2)) -> cons(X1, X2) cons(active(X1), X2) -> cons(X1, X2) cons(X1, active(X2)) -> cons(X1, X2) take(mark(X1), X2) -> take(X1, X2) take(X1, mark(X2)) -> take(X1, X2) take(active(X1), X2) -> take(X1, X2) take(X1, active(X2)) -> take(X1, X2) length(mark(X)) -> length(X) length(active(X)) -> length(X) Q is empty. We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (44) DependencyGraphProof (EQUIVALENT) The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 0 SCCs with 2 less nodes. ---------------------------------------- (45) TRUE