YES (ignored inputs)COMMENT translated from Cops 162 *** Computating Strongly Quasi-Reducible Parts *** TRS: [ +(0,?y) -> ?y, +(s(?x),?y) -> s(+(?y,?x)), +(+(?x,?y),?z) -> +(?x,+(?y,?z)), +(?x,?y) -> +(?y,?x) ] Constructors: {0,s} Defined function symbols: {+} Constructor subsystem: [ ] Rule part & Conj Part: [ +(0,?y) -> ?y, +(s(?x),?y) -> s(+(?y,?x)) ] [ +(+(?x,?y),?z) -> +(?x,+(?y,?z)), +(?x,?y) -> +(?y,?x) ] *** Ground Confluence Check by Rewriting Induction *** Sort: {Nat} Signature: [ + : Nat,Nat -> Nat, 0 : Nat, s : Nat -> Nat ] Rule Part: [ +(0,?y) -> ?y, +(s(?x),?y) -> s(+(?y,?x)) ] Conjecture Part: [ +(+(?x,?y),?z) = +(?x,+(?y,?z)), +(?x,?y) = +(?y,?x) ] Precedence (by weight): {(+,3),(0,2),(s,0)} Rule part is confluent. R0 is ground confluent. Check conj part consists of inductive theorems of R0. Rules: [ +(0,?y) -> ?y, +(s(?x),?y) -> s(+(?y,?x)) ] Conjectures: [ +(+(?x,?y),?z) = +(?x,+(?y,?z)), +(?x,?y) = +(?y,?x) ] STEP 0 ES: [ +(+(?x,?y),?z) = +(?x,+(?y,?z)), +(?x,?y) = +(?y,?x) ] HS: [ ] ES0: [ +(+(?x,?y),?z) = +(?x,+(?y,?z)), +(?x,?y) = +(?y,?x) ] HS0: [ ] ES1: [ +(+(?x,?y),?z) = +(?x,+(?y,?z)), +(?x,?y) = +(?y,?x) ] HS1: [ ] Expand +(?x,?y) = +(?y,?x) [ ?y_1 = +(?y_1,0), s(+(?y_2,?x_2)) = +(?y_2,s(?x_2)) ] ES2: [ ?y_1 = +(?y_1,0), s(+(?y_2,?x_2)) = +(?y_2,s(?x_2)), +(+(?x,?y),?z) = +(?x,+(?y,?z)) ] HS2: [ +(?x,?y) -> +(?y,?x) ] STEP 1 ES: [ ?y_1 = +(?y_1,0), s(+(?y_2,?x_2)) = +(?y_2,s(?x_2)), +(+(?x,?y),?z) = +(?x,+(?y,?z)) ] HS: [ +(?x,?y) -> +(?y,?x) ] ES0: [ ?y_1 = +(?y_1,0), s(+(?y_2,?x_2)) = +(?y_2,s(?x_2)), +(+(?x,?y),?z) = +(?x,+(?y,?z)) ] HS0: [ +(?x,?y) -> +(?y,?x) ] ES1: [ ?y_1 = +(?y_1,0), s(+(?y_2,?x_2)) = +(?y_2,s(?x_2)), +(+(?x,?y),?z) = +(?x,+(?y,?z)) ] HS1: [ +(?x,?y) -> +(?y,?x) ] Expand +(?y_1,0) = ?y_1 [ 0 = 0, s(+(0,?x_2)) = s(?x_2) ] ES2: [ 0 = 0, s(?x_2) = s(?x_2), +(+(?x,?y),?z) = +(?x,+(?y,?z)), s(+(?y_2,?x_2)) = +(?y_2,s(?x_2)) ] HS2: [ +(?y_1,0) -> ?y_1, +(?x,?y) -> +(?y,?x) ] STEP 2 ES: [ 0 = 0, s(?x_2) = s(?x_2), +(+(?x,?y),?z) = +(?x,+(?y,?z)), s(+(?y_2,?x_2)) = +(?y_2,s(?x_2)) ] HS: [ +(?y_1,0) -> ?y_1, +(?x,?y) -> +(?y,?x) ] ES0: [ 0 = 0, s(?x_2) = s(?x_2), +(+(?x,?y),?z) = +(?x,+(?y,?z)), s(+(?y_2,?x_2)) = +(?y_2,s(?x_2)) ] HS0: [ +(?y_1,0) -> ?y_1, +(?x,?y) -> +(?y,?x) ] ES1: [ +(+(?x,?y),?z) = +(?x,+(?y,?z)), s(+(?y_2,?x_2)) = +(?y_2,s(?x_2)) ] HS1: [ +(?y_1,0) -> ?y_1, +(?x,?y) -> +(?y,?x) ] Expand +(?y_2,s(?x_2)) = s(+(?y_2,?x_2)) [ s(?x) = s(+(0,?x)), s(+(s(?x),?x_2)) = s(+(s(?x_2),?x)) ] ES2: [ s(?x) = s(+(0,?x)), s(s(+(?x_2,?x))) = s(+(s(?x_2),?x)), +(+(?x,?y),?z) = +(?x,+(?y,?z)) ] HS2: [ +(?y_2,s(?x_2)) -> s(+(?y_2,?x_2)), +(?y_1,0) -> ?y_1, +(?x,?y) -> +(?y,?x) ] STEP 3 ES: [ s(?x) = s(+(0,?x)), s(s(+(?x_2,?x))) = s(+(s(?x_2),?x)), +(+(?x,?y),?z) = +(?x,+(?y,?z)) ] HS: [ +(?y_2,s(?x_2)) -> s(+(?y_2,?x_2)), +(?y_1,0) -> ?y_1, +(?x,?y) -> +(?y,?x) ] ES0: [ s(?x) = s(?x), s(s(+(?x_2,?x))) = s(s(+(?x,?x_2))), +(+(?x,?y),?z) = +(?x,+(?y,?z)) ] HS0: [ +(?y_2,s(?x_2)) -> s(+(?y_2,?x_2)), +(?y_1,0) -> ?y_1, +(?x,?y) -> +(?y,?x) ] ES1: [ +(+(?x,?y),?z) = +(?x,+(?y,?z)) ] HS1: [ +(?y_2,s(?x_2)) -> s(+(?y_2,?x_2)), +(?y_1,0) -> ?y_1, +(?x,?y) -> +(?y,?x) ] Expand +(+(?x,?y),?z) = +(?x,+(?y,?z)) [ +(?y_1,?z) = +(0,+(?y_1,?z)), +(s(+(?y_2,?x_2)),?z) = +(s(?x_2),+(?y_2,?z)) ] ES2: [ +(?y_1,?z) = +(0,+(?y_1,?z)), s(+(?z,+(?y_2,?x_2))) = +(s(?x_2),+(?y_2,?z)) ] HS2: [ +(+(?x,?y),?z) -> +(?x,+(?y,?z)), +(?y_2,s(?x_2)) -> s(+(?y_2,?x_2)), +(?y_1,0) -> ?y_1, +(?x,?y) -> +(?y,?x) ] STEP 4 ES: [ +(?y_1,?z) = +(0,+(?y_1,?z)), s(+(?z,+(?y_2,?x_2))) = +(s(?x_2),+(?y_2,?z)) ] HS: [ +(+(?x,?y),?z) -> +(?x,+(?y,?z)), +(?y_2,s(?x_2)) -> s(+(?y_2,?x_2)), +(?y_1,0) -> ?y_1, +(?x,?y) -> +(?y,?x) ] ES0: [ +(?y_1,?z) = +(?y_1,?z), s(+(?z,+(?y_2,?x_2))) = s(+(+(?y_2,?z),?x_2)) ] HS0: [ +(+(?x,?y),?z) -> +(?x,+(?y,?z)), +(?y_2,s(?x_2)) -> s(+(?y_2,?x_2)), +(?y_1,0) -> ?y_1, +(?x,?y) -> +(?y,?x) ] ES1: [ s(+(?z,+(?y_2,?x_2))) = s(+(+(?y_2,?z),?x_2)) ] HS1: [ +(+(?x,?y),?z) -> +(?x,+(?y,?z)), +(?y_2,s(?x_2)) -> s(+(?y_2,?x_2)), +(?y_1,0) -> ?y_1, +(?x,?y) -> +(?y,?x) ] Expand s(+(?z,+(?y_2,?x_2))) = s(+(+(?y_2,?z),?x_2)) [ s(+(?z,?y_3)) = s(+(+(0,?z),?y_3)), s(+(?z,s(+(?y_4,?x_4)))) = s(+(+(s(?x_4),?z),?y_4)) ] ES2: [ s(+(?z,?y_3)) = s(+(+(0,?z),?y_3)), s(s(+(?z,+(?y_4,?x_4)))) = s(+(+(s(?x_4),?z),?y_4)) ] HS2: [ s(+(?z,+(?y_2,?x_2))) -> s(+(+(?y_2,?z),?x_2)), +(+(?x,?y),?z) -> +(?x,+(?y,?z)), +(?y_2,s(?x_2)) -> s(+(?y_2,?x_2)), +(?y_1,0) -> ?y_1, +(?x,?y) -> +(?y,?x) ] STEP 5 ES: [ s(+(?z,?y_3)) = s(+(+(0,?z),?y_3)), s(s(+(?z,+(?y_4,?x_4)))) = s(+(+(s(?x_4),?z),?y_4)) ] HS: [ s(+(?z,+(?y_2,?x_2))) -> s(+(+(?y_2,?z),?x_2)), +(+(?x,?y),?z) -> +(?x,+(?y,?z)), +(?y_2,s(?x_2)) -> s(+(?y_2,?x_2)), +(?y_1,0) -> ?y_1, +(?x,?y) -> +(?y,?x) ] ES0: [ s(+(?z,?y_3)) = s(+(?z,?y_3)), s(s(+(?z,+(?y_4,?x_4)))) = s(s(+(?y_4,+(?z,?x_4)))) ] HS0: [ s(+(?z,+(?y_2,?x_2))) -> s(+(+(?y_2,?z),?x_2)), +(+(?x,?y),?z) -> +(?x,+(?y,?z)), +(?y_2,s(?x_2)) -> s(+(?y_2,?x_2)), +(?y_1,0) -> ?y_1, +(?x,?y) -> +(?y,?x) ] ES1: [ s(s(+(?z,+(?y_4,?x_4)))) = s(s(+(?y_4,+(?z,?x_4)))) ] HS1: [ s(+(?z,+(?y_2,?x_2))) -> s(+(+(?y_2,?z),?x_2)), +(+(?x,?y),?z) -> +(?x,+(?y,?z)), +(?y_2,s(?x_2)) -> s(+(?y_2,?x_2)), +(?y_1,0) -> ?y_1, +(?x,?y) -> +(?y,?x) ] Expand s(s(+(?z,+(?y_4,?x_4)))) = s(s(+(?y_4,+(?z,?x_4)))) [ s(s(+(?z,?y_5))) = s(s(+(0,+(?z,?y_5)))), s(s(+(?z,s(+(?y_6,?x_6))))) = s(s(+(s(?x_6),+(?z,?y_6)))) ] ES2: [ s(s(+(?z,?y_5))) = s(s(+(0,+(?z,?y_5)))), s(s(s(+(?z,+(?y_6,?x_6))))) = s(s(+(s(?x_6),+(?z,?y_6)))) ] HS2: [ s(s(+(?z,+(?y_4,?x_4)))) -> s(s(+(?y_4,+(?z,?x_4)))), s(+(?z,+(?y_2,?x_2))) -> s(+(+(?y_2,?z),?x_2)), +(+(?x,?y),?z) -> +(?x,+(?y,?z)), +(?y_2,s(?x_2)) -> s(+(?y_2,?x_2)), +(?y_1,0) -> ?y_1, +(?x,?y) -> +(?y,?x) ] STEP 6 ES: [ s(s(+(?z,?y_5))) = s(s(+(0,+(?z,?y_5)))), s(s(s(+(?z,+(?y_6,?x_6))))) = s(s(+(s(?x_6),+(?z,?y_6)))) ] HS: [ s(s(+(?z,+(?y_4,?x_4)))) -> s(s(+(?y_4,+(?z,?x_4)))), s(+(?z,+(?y_2,?x_2))) -> s(+(+(?y_2,?z),?x_2)), +(+(?x,?y),?z) -> +(?x,+(?y,?z)), +(?y_2,s(?x_2)) -> s(+(?y_2,?x_2)), +(?y_1,0) -> ?y_1, +(?x,?y) -> +(?y,?x) ] ES0: [ s(s(+(?z,?y_5))) = s(s(+(?z,?y_5))), s(s(s(+(?z,+(?y_6,?x_6))))) = s(s(s(+(+(?z,?y_6),?x_6)))) ] HS0: [ s(s(+(?z,+(?y_4,?x_4)))) -> s(s(+(?y_4,+(?z,?x_4)))), s(+(?z,+(?y_2,?x_2))) -> s(+(+(?y_2,?z),?x_2)), +(+(?x,?y),?z) -> +(?x,+(?y,?z)), +(?y_2,s(?x_2)) -> s(+(?y_2,?x_2)), +(?y_1,0) -> ?y_1, +(?x,?y) -> +(?y,?x) ] ES1: [ ] HS1: [ s(s(+(?z,+(?y_4,?x_4)))) -> s(s(+(?y_4,+(?z,?x_4)))), s(+(?z,+(?y_2,?x_2))) -> s(+(+(?y_2,?z),?x_2)), +(+(?x,?y),?z) -> +(?x,+(?y,?z)), +(?y_2,s(?x_2)) -> s(+(?y_2,?x_2)), +(?y_1,0) -> ?y_1, +(?x,?y) -> +(?y,?x) ] Conj part consisits of inductive theorems of R0. examples/fromCops/cr/162.trs: Success(GCR) (10 msec.)