(ignored inputs)COMMENT submitted by: Johannes Waldmann Rewrite Rules: [ c(b(?x)) -> a(c(?x)), b(a(?x)) -> c(c(?x)), b(c(?x)) -> c(a(?x)), c(c(?x)) -> a(b(?x)), b(c(?x)) -> a(c(?x)), c(a(?x)) -> b(c(?x)), b(b(?x)) -> c(a(?x)), a(a(?x)) -> a(b(?x)) ] Apply Direct Methods... Inner CPs: [ c(c(c(?x_1))) = a(c(a(?x_1))), c(c(a(?x_2))) = a(c(c(?x_2))), c(a(c(?x_4))) = a(c(c(?x_4))), c(c(a(?x_6))) = a(c(b(?x_6))), b(a(b(?x_7))) = c(c(a(?x_7))), b(a(c(?x))) = c(a(b(?x))), b(a(b(?x_3))) = c(a(c(?x_3))), b(b(c(?x_5))) = c(a(a(?x_5))), c(a(c(?x))) = a(b(b(?x))), c(b(c(?x_5))) = a(b(a(?x_5))), b(a(c(?x))) = a(c(b(?x))), b(a(b(?x_3))) = a(c(c(?x_3))), b(b(c(?x_5))) = a(c(a(?x_5))), c(a(b(?x_7))) = b(c(a(?x_7))), b(c(c(?x_1))) = c(a(a(?x_1))), b(c(a(?x_2))) = c(a(c(?x_2))), b(a(c(?x_4))) = c(a(c(?x_4))), c(a(b(?x))) = a(b(c(?x))), b(c(a(?x))) = c(a(b(?x))), a(a(b(?x))) = a(b(a(?x))) ] Outer CPs: [ c(a(?x_2)) = a(c(?x_2)) ] not Overlay, check Termination... unknown/not Terminating unknown Knuth & Bendix Linear unknown Development Closed unknown Strongly Closed unknown Weakly-Non-Overlapping & Non-Collapsing & Shallow unknown Upside-Parallel-Closed/Outside-Closed (inner) Parallel CPs: (not computed) unknown Toyama (Parallel CPs) Simultaneous CPs: [ c(c(c(?x_2))) = a(c(a(?x_2))), c(c(a(?x_3))) = a(c(c(?x_3))), c(a(c(?x_5))) = a(c(c(?x_5))), c(c(a(?x_7))) = a(c(b(?x_7))), c(a(c(c(?x_2)))) = b(a(c(a(?x_2)))), c(a(c(a(?x_3)))) = b(a(c(c(?x_3)))), c(a(a(c(?x_5)))) = b(a(c(c(?x_5)))), c(a(c(a(?x_7)))) = b(a(c(b(?x_7)))), a(b(c(c(?x_2)))) = c(a(c(a(?x_2)))), a(b(c(a(?x_3)))) = c(a(c(c(?x_3)))), a(b(a(c(?x_5)))) = c(a(c(c(?x_5)))), a(b(c(a(?x_7)))) = c(a(c(b(?x_7)))), a(c(c(c(?x_2)))) = b(a(c(a(?x_2)))), a(c(c(a(?x_3)))) = b(a(c(c(?x_3)))), a(c(a(c(?x_5)))) = b(a(c(c(?x_5)))), a(c(c(a(?x_7)))) = b(a(c(b(?x_7)))), c(a(b(?x))) = b(a(c(?x))), a(b(b(?x))) = c(a(c(?x))), a(c(b(?x))) = b(a(c(?x))), b(a(b(?x_8))) = c(c(a(?x_8))), a(c(a(b(?x_8)))) = c(c(c(a(?x_8)))), c(a(a(b(?x_8)))) = b(c(c(a(?x_8)))), a(c(a(?x))) = c(c(c(?x))), c(a(a(?x))) = b(c(c(?x))), a(c(?x)) = c(a(?x)), b(a(c(?x_2))) = c(a(b(?x_2))), b(a(b(?x_4))) = c(a(c(?x_4))), b(b(c(?x_6))) = c(a(a(?x_6))), a(c(a(c(?x_2)))) = c(c(a(b(?x_2)))), a(c(a(b(?x_4)))) = c(c(a(c(?x_4)))), a(c(b(c(?x_6)))) = c(c(a(a(?x_6)))), c(a(a(c(?x_2)))) = b(c(a(b(?x_2)))), c(a(a(b(?x_4)))) = b(c(a(c(?x_4)))), c(a(b(c(?x_6)))) = b(c(a(a(?x_6)))), a(c(c(?x))) = c(c(a(?x))), c(a(c(?x))) = b(c(a(?x))), c(a(b(?x_1))) = a(b(c(?x_1))), c(a(c(?x_2))) = a(b(b(?x_2))), c(b(c(?x_6))) = a(b(a(?x_6))), a(b(a(b(?x_1)))) = c(a(b(c(?x_1)))), a(b(a(c(?x_2)))) = c(a(b(b(?x_2)))), a(b(b(c(?x_6)))) = c(a(b(a(?x_6)))), c(a(a(b(?x_1)))) = b(a(b(c(?x_1)))), c(a(a(c(?x_2)))) = b(a(b(b(?x_2)))), c(a(b(c(?x_6)))) = b(a(b(a(?x_6)))), a(c(a(b(?x_1)))) = b(a(b(c(?x_1)))), a(c(a(c(?x_2)))) = b(a(b(b(?x_2)))), a(c(b(c(?x_6)))) = b(a(b(a(?x_6)))), a(b(c(?x))) = c(a(b(?x))), c(a(c(?x))) = b(a(b(?x))), a(c(c(?x))) = b(a(b(?x))), c(a(?x)) = a(c(?x)), b(a(c(?x_2))) = a(c(b(?x_2))), b(a(b(?x_5))) = a(c(c(?x_5))), b(b(c(?x_6))) = a(c(a(?x_6))), a(c(a(c(?x_2)))) = c(a(c(b(?x_2)))), a(c(a(b(?x_5)))) = c(a(c(c(?x_5)))), a(c(b(c(?x_6)))) = c(a(c(a(?x_6)))), c(a(a(c(?x_2)))) = b(a(c(b(?x_2)))), c(a(a(b(?x_5)))) = b(a(c(c(?x_5)))), c(a(b(c(?x_6)))) = b(a(c(a(?x_6)))), a(c(c(?x))) = c(a(c(?x))), c(a(c(?x))) = b(a(c(?x))), c(a(b(?x_8))) = b(c(a(?x_8))), c(a(a(b(?x_8)))) = b(b(c(a(?x_8)))), a(b(a(b(?x_8)))) = c(b(c(a(?x_8)))), a(c(a(b(?x_8)))) = b(b(c(a(?x_8)))), c(a(a(?x))) = b(b(c(?x))), a(b(a(?x))) = c(b(c(?x))), a(c(a(?x))) = b(b(c(?x))), b(c(a(?x_1))) = c(a(b(?x_1))), b(c(c(?x_3))) = c(a(a(?x_3))), b(c(a(?x_4))) = c(a(c(?x_4))), b(a(c(?x_6))) = c(a(c(?x_6))), c(a(c(a(?x_1)))) = b(c(a(b(?x_1)))), c(a(c(c(?x_3)))) = b(c(a(a(?x_3)))), c(a(c(a(?x_4)))) = b(c(a(c(?x_4)))), c(a(a(c(?x_6)))) = b(c(a(c(?x_6)))), a(c(c(a(?x_1)))) = c(c(a(b(?x_1)))), a(c(c(c(?x_3)))) = c(c(a(a(?x_3)))), a(c(c(a(?x_4)))) = c(c(a(c(?x_4)))), a(c(a(c(?x_6)))) = c(c(a(c(?x_6)))), a(c(b(?x))) = c(c(a(?x))), a(a(b(?x_1))) = a(b(a(?x_1))), a(b(a(b(?x_1)))) = a(a(b(a(?x_1)))), c(c(a(b(?x_1)))) = b(a(b(a(?x_1)))), b(c(a(b(?x_1)))) = c(a(b(a(?x_1)))), a(b(a(?x))) = a(a(b(?x))), c(c(a(?x))) = b(a(b(?x))) ] unknown Okui (Simultaneous CPs) unknown Strongly Depth-Preserving & Root-E-Closed/Non-E-Overlapping unknown Strongly Weight-Preserving & Root-E-Closed/Non-E-Overlapping check Locally Decreasing Diagrams by Rule Labelling... Critical Pair by Rules <1, 0> preceded by [(c,1)] joinable by a reduction of rules <[([],3)], [([(a,1)],5)]> Critical Pair by Rules <2, 0> preceded by [(c,1)] joinable by a reduction of rules <[([(c,1)],5),([],0)], []> joinable by a reduction of rules <[([],3),([(a,1)],1)], []> Critical Pair by Rules <4, 0> preceded by [(c,1)] joinable by a reduction of rules <[([],5),([],4)], []> Critical Pair by Rules <6, 0> preceded by [(c,1)] joinable by a reduction of rules <[([(c,1)],5),([],0),([(a,1)],3),([],7),([(a,1)],6)], [([(a,1)],0),([],7),([(a,1)],2)]> joinable by a reduction of rules <[([],3),([(a,1)],1),([(a,1)],3),([],7),([(a,1)],6)], [([(a,1)],0),([],7),([(a,1)],2)]> Critical Pair by Rules <7, 1> preceded by [(b,1)] joinable by a reduction of rules <[([],1),([(c,1)],0)], [([(c,1)],5),([(c,1)],4)]> Critical Pair by Rules <0, 2> preceded by [(b,1)] joinable by a reduction of rules <[([],1),([(c,1)],3)], []> joinable by a reduction of rules <[], [([],5),([(b,1)],0)]> Critical Pair by Rules <3, 2> preceded by [(b,1)] joinable by a reduction of rules <[([],1),([(c,1)],0)], []> joinable by a reduction of rules <[], [([],5),([(b,1)],3)]> Critical Pair by Rules <5, 2> preceded by [(b,1)] joinable by a reduction of rules <[([(b,1)],2)], [([],5)]> Critical Pair by Rules <0, 3> preceded by [(c,1)] joinable by a reduction of rules <[([],5),([(b,1)],3),([],1),([],3)], []> joinable by a reduction of rules <[([],5),([],4),([(a,1)],3),([],7)], []> Critical Pair by Rules <5, 3> preceded by [(c,1)] joinable by a reduction of rules <[([],0)], [([(a,1)],1)]> Critical Pair by Rules <0, 4> preceded by [(b,1)] joinable by a reduction of rules <[([],1),([],3)], [([(a,1)],0),([],7)]> Critical Pair by Rules <3, 4> preceded by [(b,1)] joinable by a reduction of rules <[([],1),([],3)], [([(a,1)],3),([],7)]> Critical Pair by Rules <5, 4> preceded by [(b,1)] joinable by a reduction of rules <[([(b,1)],2),([],4)], []> Critical Pair by Rules <7, 5> preceded by [(c,1)] joinable by a reduction of rules <[], [([],2),([(c,1)],7)]> joinable by a reduction of rules <[([],5),([(b,1)],0)], [([(b,1)],5),([(b,1)],4)]> Critical Pair by Rules <1, 6> preceded by [(b,1)] joinable by a reduction of rules <[([],2)], [([],5),([(b,1)],5),([],6)]> joinable by a reduction of rules <[([(b,1)],3),([],1),([(c,1)],0)], [([],5),([(b,1)],5),([],6)]> Critical Pair by Rules <2, 6> preceded by [(b,1)] joinable by a reduction of rules <[([(b,1)],5),([],6)], []> Critical Pair by Rules <4, 6> preceded by [(b,1)] joinable by a reduction of rules <[([],1),([],3),([(a,1)],2)], [([],5),([(b,1)],3),([],1),([],3),([(a,1)],6)]> joinable by a reduction of rules <[([],1),([],3),([(a,1)],2)], [([],5),([],4),([(a,1)],3),([],7),([(a,1)],6)]> Critical Pair by Rules <3, 3> preceded by [(c,1)] joinable by a reduction of rules <[([],5),([],4),([(a,1)],0)], [([(a,1)],4)]> Critical Pair by Rules <6, 6> preceded by [(b,1)] joinable by a reduction of rules <[([],2),([(c,1)],7)], []> joinable by a reduction of rules <[([(b,1)],5),([(b,1)],4)], [([],5),([(b,1)],0)]> Critical Pair by Rules <7, 7> preceded by [(a,1)] joinable by a reduction of rules <[], [([(a,1)],1),([(a,1)],3)]> Critical Pair by Rules <4, 2> preceded by [] joinable by a reduction of rules <[], [([],5),([],4)]> unknown Diagram Decreasing check Non-Confluence... obtain 13 rules by 3 steps unfolding obtain 100 candidates for checking non-joinability check by TCAP-Approximation (failure) check by Ordering(rpo), check by Tree-Automata Approximation (failure) check by Interpretation(mod2) (failure) check by Descendants-Approximation, check by Ordering(poly) (failure) unknown Non-Confluence unknown Huet (modulo AC) check by Reduction-Preserving Completion... STEP: 1 (parallel) S: [ c(b(?x)) -> a(c(?x)), b(a(?x)) -> c(c(?x)), c(c(?x)) -> a(b(?x)), b(c(?x)) -> a(c(?x)), b(b(?x)) -> c(a(?x)), a(a(?x)) -> a(b(?x)) ] P: [ b(c(?x)) -> c(a(?x)), c(a(?x)) -> b(c(?x)) ] S: unknown termination failure(Step 1) STEP: 2 (linear) S: [ c(b(?x)) -> a(c(?x)), b(a(?x)) -> c(c(?x)), c(c(?x)) -> a(b(?x)), b(c(?x)) -> a(c(?x)), b(b(?x)) -> c(a(?x)), a(a(?x)) -> a(b(?x)) ] P: [ b(c(?x)) -> c(a(?x)), c(a(?x)) -> b(c(?x)) ] S: unknown termination failure(Step 2) STEP: 3 (relative) S: [ c(b(?x)) -> a(c(?x)), b(a(?x)) -> c(c(?x)), c(c(?x)) -> a(b(?x)), b(c(?x)) -> a(c(?x)), b(b(?x)) -> c(a(?x)), a(a(?x)) -> a(b(?x)) ] P: [ b(c(?x)) -> c(a(?x)), c(a(?x)) -> b(c(?x)) ] Check relative termination: [ c(b(?x)) -> a(c(?x)), b(a(?x)) -> c(c(?x)), c(c(?x)) -> a(b(?x)), b(c(?x)) -> a(c(?x)), b(b(?x)) -> c(a(?x)), a(a(?x)) -> a(b(?x)) ] [ b(c(?x)) -> c(a(?x)), c(a(?x)) -> b(c(?x)) ] Polynomial Interpretation: a:= (2)*x1 b:= (4)+(2)*x1 c:= (2)*x1 retract c(b(?x)) -> a(c(?x)) retract b(a(?x)) -> c(c(?x)) retract b(c(?x)) -> a(c(?x)) retract b(b(?x)) -> c(a(?x)) retract b(c(?x)) -> c(a(?x)) Polynomial Interpretation: a:= (2)+(1)*x1*x1 b:= (1)*x1*x1 c:= (2)+(1)*x1*x1 relatively terminating S/P: relatively terminating check CP condition: failed failure(Step 3) failure(no possibility remains) unknown Reduction-Preserving Completion Direct Methods: Can't judge Try Persistent Decomposition for... [ c(b(?x)) -> a(c(?x)), b(a(?x)) -> c(c(?x)), b(c(?x)) -> c(a(?x)), c(c(?x)) -> a(b(?x)), b(c(?x)) -> a(c(?x)), c(a(?x)) -> b(c(?x)), b(b(?x)) -> c(a(?x)), a(a(?x)) -> a(b(?x)) ] Sort Assignment: a : 15=>15 b : 15=>15 c : 15=>15 maximal types: {15} Persistent Decomposition failed: Can't judge Try Layer Preserving Decomposition for... [ c(b(?x)) -> a(c(?x)), b(a(?x)) -> c(c(?x)), b(c(?x)) -> c(a(?x)), c(c(?x)) -> a(b(?x)), b(c(?x)) -> a(c(?x)), c(a(?x)) -> b(c(?x)), b(b(?x)) -> c(a(?x)), a(a(?x)) -> a(b(?x)) ] Layer Preserving Decomposition failed: Can't judge Try Commutative Decomposition for... [ c(b(?x)) -> a(c(?x)), b(a(?x)) -> c(c(?x)), b(c(?x)) -> c(a(?x)), c(c(?x)) -> a(b(?x)), b(c(?x)) -> a(c(?x)), c(a(?x)) -> b(c(?x)), b(b(?x)) -> c(a(?x)), a(a(?x)) -> a(b(?x)) ] Outside Critical Pair: by Rules <4, 2> develop reducts from lhs term... <{}, a(c(?x_4))> develop reducts from rhs term... <{5}, b(c(?x_4))> <{}, c(a(?x_4))> Inside Critical Pair: by Rules <1, 0> develop reducts from lhs term... <{3}, a(b(c(?x_1)))> <{3}, c(a(b(?x_1)))> <{}, c(c(c(?x_1)))> develop reducts from rhs term... <{5}, a(b(c(?x_1)))> <{}, a(c(a(?x_1)))> Inside Critical Pair: by Rules <2, 0> develop reducts from lhs term... <{3}, a(b(a(?x_2)))> <{5}, c(b(c(?x_2)))> <{}, c(c(a(?x_2)))> develop reducts from rhs term... <{3}, a(a(b(?x_2)))> <{}, a(c(c(?x_2)))> Inside Critical Pair: by Rules <4, 0> develop reducts from lhs term... <{5}, b(c(c(?x_4)))> <{}, c(a(c(?x_4)))> develop reducts from rhs term... <{3}, a(a(b(?x_4)))> <{}, a(c(c(?x_4)))> Inside Critical Pair: by Rules <6, 0> develop reducts from lhs term... <{3}, a(b(a(?x_6)))> <{5}, c(b(c(?x_6)))> <{}, c(c(a(?x_6)))> develop reducts from rhs term... <{0}, a(a(c(?x_6)))> <{}, a(c(b(?x_6)))> Inside Critical Pair: by Rules <7, 1> develop reducts from lhs term... <{1}, c(c(b(?x_7)))> <{}, b(a(b(?x_7)))> develop reducts from rhs term... <{3}, a(b(a(?x_7)))> <{5}, c(b(c(?x_7)))> <{}, c(c(a(?x_7)))> Inside Critical Pair: by Rules <0, 2> develop reducts from lhs term... <{1}, c(c(c(?x)))> <{}, b(a(c(?x)))> develop reducts from rhs term... <{5}, b(c(b(?x)))> <{}, c(a(b(?x)))> Inside Critical Pair: by Rules <3, 2> develop reducts from lhs term... <{1}, c(c(b(?x_3)))> <{}, b(a(b(?x_3)))> develop reducts from rhs term... <{5}, b(c(c(?x_3)))> <{}, c(a(c(?x_3)))> Inside Critical Pair: by Rules <5, 2> develop reducts from lhs term... <{6}, c(a(c(?x_5)))> <{4}, b(a(c(?x_5)))> <{2}, b(c(a(?x_5)))> <{}, b(b(c(?x_5)))> develop reducts from rhs term... <{5}, b(c(a(?x_5)))> <{7}, c(a(b(?x_5)))> <{}, c(a(a(?x_5)))> Inside Critical Pair: by Rules <0, 3> develop reducts from lhs term... <{5}, b(c(c(?x)))> <{}, c(a(c(?x)))> develop reducts from rhs term... <{6}, a(c(a(?x)))> <{}, a(b(b(?x)))> Inside Critical Pair: by Rules <5, 3> develop reducts from lhs term... <{0}, a(c(c(?x_5)))> <{4}, c(a(c(?x_5)))> <{2}, c(c(a(?x_5)))> <{}, c(b(c(?x_5)))> develop reducts from rhs term... <{1}, a(c(c(?x_5)))> <{}, a(b(a(?x_5)))> Inside Critical Pair: by Rules <0, 4> develop reducts from lhs term... <{1}, c(c(c(?x)))> <{}, b(a(c(?x)))> develop reducts from rhs term... <{0}, a(a(c(?x)))> <{}, a(c(b(?x)))> Inside Critical Pair: by Rules <3, 4> develop reducts from lhs term... <{1}, c(c(b(?x_3)))> <{}, b(a(b(?x_3)))> develop reducts from rhs term... <{3}, a(a(b(?x_3)))> <{}, a(c(c(?x_3)))> Inside Critical Pair: by Rules <5, 4> develop reducts from lhs term... <{6}, c(a(c(?x_5)))> <{4}, b(a(c(?x_5)))> <{2}, b(c(a(?x_5)))> <{}, b(b(c(?x_5)))> develop reducts from rhs term... <{5}, a(b(c(?x_5)))> <{}, a(c(a(?x_5)))> Inside Critical Pair: by Rules <7, 5> develop reducts from lhs term... <{5}, b(c(b(?x_7)))> <{}, c(a(b(?x_7)))> develop reducts from rhs term... <{4}, a(c(a(?x_7)))> <{2}, c(a(a(?x_7)))> <{5}, b(b(c(?x_7)))> <{}, b(c(a(?x_7)))> Inside Critical Pair: by Rules <1, 6> develop reducts from lhs term... <{4}, a(c(c(?x_1)))> <{2}, c(a(c(?x_1)))> <{3}, b(a(b(?x_1)))> <{}, b(c(c(?x_1)))> develop reducts from rhs term... <{5}, b(c(a(?x_1)))> <{7}, c(a(b(?x_1)))> <{}, c(a(a(?x_1)))> Inside Critical Pair: by Rules <2, 6> develop reducts from lhs term... <{4}, a(c(a(?x_2)))> <{2}, c(a(a(?x_2)))> <{5}, b(b(c(?x_2)))> <{}, b(c(a(?x_2)))> develop reducts from rhs term... <{5}, b(c(c(?x_2)))> <{}, c(a(c(?x_2)))> Inside Critical Pair: by Rules <4, 6> develop reducts from lhs term... <{1}, c(c(c(?x_4)))> <{}, b(a(c(?x_4)))> develop reducts from rhs term... <{5}, b(c(c(?x_4)))> <{}, c(a(c(?x_4)))> Commutative Decomposition failed: Can't judge No further decomposition possible Combined result: Can't judge 1004.trs: Failure(unknown CR) MAYBE (6523 msec.)