NO proof of Strategy_removed_CSR_05_ExIntrod_GM04.trs # AProVE Commit ID: c69e44bd14796315568835c1ffa2502984884775 jera 20211004 unpublished Termination w.r.t. Q of the given QTRS could be disproven: (0) QTRS (1) QTRSRRRProof [EQUIVALENT, 64 ms] (2) QTRS (3) Overlay + Local Confluence [EQUIVALENT, 0 ms] (4) QTRS (5) DependencyPairsProof [EQUIVALENT, 0 ms] (6) QDP (7) DependencyGraphProof [EQUIVALENT, 0 ms] (8) AND (9) QDP (10) UsableRulesProof [EQUIVALENT, 0 ms] (11) QDP (12) QReductionProof [EQUIVALENT, 0 ms] (13) QDP (14) QDPSizeChangeProof [EQUIVALENT, 0 ms] (15) YES (16) QDP (17) UsableRulesProof [EQUIVALENT, 0 ms] (18) QDP (19) QReductionProof [EQUIVALENT, 0 ms] (20) QDP (21) QDPSizeChangeProof [EQUIVALENT, 0 ms] (22) YES (23) QDP (24) UsableRulesProof [EQUIVALENT, 0 ms] (25) QDP (26) QReductionProof [EQUIVALENT, 0 ms] (27) QDP (28) NonTerminationLoopProof [COMPLETE, 0 ms] (29) NO ---------------------------------------- (0) Obligation: Q restricted rewrite system: The TRS R consists of the following rules: nats -> adx(zeros) zeros -> cons(0, zeros) incr(cons(X, Y)) -> cons(s(X), incr(Y)) adx(cons(X, Y)) -> incr(cons(X, adx(Y))) hd(cons(X, Y)) -> X tl(cons(X, Y)) -> Y Q is empty. ---------------------------------------- (1) QTRSRRRProof (EQUIVALENT) Used ordering: Polynomial interpretation [POLO]: POL(0) = 0 POL(adx(x_1)) = 2*x_1 POL(cons(x_1, x_2)) = 2*x_1 + 2*x_2 POL(hd(x_1)) = 2 + x_1 POL(incr(x_1)) = x_1 POL(nats) = 2 POL(s(x_1)) = x_1 POL(tl(x_1)) = 2 + 2*x_1 POL(zeros) = 0 With this ordering the following rules can be removed by the rule removal processor [LPAR04] because they are oriented strictly: nats -> adx(zeros) hd(cons(X, Y)) -> X tl(cons(X, Y)) -> Y ---------------------------------------- (2) Obligation: Q restricted rewrite system: The TRS R consists of the following rules: zeros -> cons(0, zeros) incr(cons(X, Y)) -> cons(s(X), incr(Y)) adx(cons(X, Y)) -> incr(cons(X, adx(Y))) Q is empty. ---------------------------------------- (3) Overlay + Local Confluence (EQUIVALENT) The TRS is overlay and locally confluent. By [NOC] we can switch to innermost. ---------------------------------------- (4) Obligation: Q restricted rewrite system: The TRS R consists of the following rules: zeros -> cons(0, zeros) incr(cons(X, Y)) -> cons(s(X), incr(Y)) adx(cons(X, Y)) -> incr(cons(X, adx(Y))) The set Q consists of the following terms: zeros incr(cons(x0, x1)) adx(cons(x0, x1)) ---------------------------------------- (5) DependencyPairsProof (EQUIVALENT) Using Dependency Pairs [AG00,LPAR04] we result in the following initial DP problem. ---------------------------------------- (6) Obligation: Q DP problem: The TRS P consists of the following rules: ZEROS -> ZEROS INCR(cons(X, Y)) -> INCR(Y) ADX(cons(X, Y)) -> INCR(cons(X, adx(Y))) ADX(cons(X, Y)) -> ADX(Y) The TRS R consists of the following rules: zeros -> cons(0, zeros) incr(cons(X, Y)) -> cons(s(X), incr(Y)) adx(cons(X, Y)) -> incr(cons(X, adx(Y))) The set Q consists of the following terms: zeros incr(cons(x0, x1)) adx(cons(x0, x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (7) DependencyGraphProof (EQUIVALENT) The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 3 SCCs with 1 less node. ---------------------------------------- (8) Complex Obligation (AND) ---------------------------------------- (9) Obligation: Q DP problem: The TRS P consists of the following rules: INCR(cons(X, Y)) -> INCR(Y) The TRS R consists of the following rules: zeros -> cons(0, zeros) incr(cons(X, Y)) -> cons(s(X), incr(Y)) adx(cons(X, Y)) -> incr(cons(X, adx(Y))) The set Q consists of the following terms: zeros incr(cons(x0, x1)) adx(cons(x0, x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (10) 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. ---------------------------------------- (11) Obligation: Q DP problem: The TRS P consists of the following rules: INCR(cons(X, Y)) -> INCR(Y) R is empty. The set Q consists of the following terms: zeros incr(cons(x0, x1)) adx(cons(x0, x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (12) 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]. zeros incr(cons(x0, x1)) adx(cons(x0, x1)) ---------------------------------------- (13) Obligation: Q DP problem: The TRS P consists of the following rules: INCR(cons(X, Y)) -> INCR(Y) R is empty. Q is empty. We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (14) 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: *INCR(cons(X, Y)) -> INCR(Y) The graph contains the following edges 1 > 1 ---------------------------------------- (15) YES ---------------------------------------- (16) Obligation: Q DP problem: The TRS P consists of the following rules: ADX(cons(X, Y)) -> ADX(Y) The TRS R consists of the following rules: zeros -> cons(0, zeros) incr(cons(X, Y)) -> cons(s(X), incr(Y)) adx(cons(X, Y)) -> incr(cons(X, adx(Y))) The set Q consists of the following terms: zeros incr(cons(x0, x1)) adx(cons(x0, x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (17) 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. ---------------------------------------- (18) Obligation: Q DP problem: The TRS P consists of the following rules: ADX(cons(X, Y)) -> ADX(Y) R is empty. The set Q consists of the following terms: zeros incr(cons(x0, x1)) adx(cons(x0, x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (19) 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]. zeros incr(cons(x0, x1)) adx(cons(x0, x1)) ---------------------------------------- (20) Obligation: Q DP problem: The TRS P consists of the following rules: ADX(cons(X, Y)) -> ADX(Y) R is empty. Q is empty. We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (21) 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: *ADX(cons(X, Y)) -> ADX(Y) The graph contains the following edges 1 > 1 ---------------------------------------- (22) YES ---------------------------------------- (23) Obligation: Q DP problem: The TRS P consists of the following rules: ZEROS -> ZEROS The TRS R consists of the following rules: zeros -> cons(0, zeros) incr(cons(X, Y)) -> cons(s(X), incr(Y)) adx(cons(X, Y)) -> incr(cons(X, adx(Y))) The set Q consists of the following terms: zeros incr(cons(x0, x1)) adx(cons(x0, x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (24) 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. ---------------------------------------- (25) Obligation: Q DP problem: The TRS P consists of the following rules: ZEROS -> ZEROS R is empty. The set Q consists of the following terms: zeros incr(cons(x0, x1)) adx(cons(x0, x1)) We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (26) 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]. zeros incr(cons(x0, x1)) adx(cons(x0, x1)) ---------------------------------------- (27) Obligation: Q DP problem: The TRS P consists of the following rules: ZEROS -> ZEROS R is empty. Q is empty. We have to consider all minimal (P,Q,R)-chains. ---------------------------------------- (28) NonTerminationLoopProof (COMPLETE) We used the non-termination processor [FROCOS05] to show that the DP problem is infinite. Found a loop by semiunifying a rule from P directly. s = ZEROS evaluates to t =ZEROS Thus s starts an infinite chain as s semiunifies with t with the following substitutions: * Matcher: [ ] * Semiunifier: [ ] -------------------------------------------------------------------------------- Rewriting sequence The DP semiunifies directly so there is only one rewrite step from ZEROS to ZEROS. ---------------------------------------- (29) NO