(ignored inputs)COMMENT submitted by: Johannes Waldmann Rewrite Rules: [ a(c(?x)) -> b(b(?x)), c(b(?x)) -> a(c(?x)), c(a(?x)) -> a(c(?x)), b(a(?x)) -> a(b(?x)), b(b(?x)) -> a(c(?x)), a(b(?x)) -> b(c(?x)), c(c(?x)) -> a(c(?x)) ] Apply Direct Methods... Inner CPs: [ a(a(c(?x_1))) = b(b(b(?x_1))), a(a(c(?x_2))) = b(b(a(?x_2))), a(a(c(?x_6))) = b(b(c(?x_6))), c(a(b(?x_3))) = a(c(a(?x_3))), c(a(c(?x_4))) = a(c(b(?x_4))), c(b(b(?x))) = a(c(c(?x))), c(b(c(?x_5))) = a(c(b(?x_5))), b(b(b(?x))) = a(b(c(?x))), b(b(c(?x_5))) = a(b(b(?x_5))), b(a(b(?x_3))) = a(c(a(?x_3))), a(a(b(?x_3))) = b(c(a(?x_3))), a(a(c(?x_4))) = b(c(b(?x_4))), c(a(c(?x_1))) = a(c(b(?x_1))), c(a(c(?x_2))) = a(c(a(?x_2))), b(a(c(?x))) = a(c(b(?x))), c(a(c(?x))) = a(c(c(?x))) ] Outer CPs: [ ] not Overlay, check Termination... unknown/not Terminating unknown Knuth & Bendix Linear unknown Development Closed unknown Strongly Closed unknown Weakly-Non-Overlapping & Non-Collapsing & Shallow inner CP cond (upside-parallel) innter CP Cond (outside) unknown Upside-Parallel-Closed/Outside-Closed (inner) Parallel CPs: (not computed) unknown Toyama (Parallel CPs) Simultaneous CPs: [ a(a(c(?x_2))) = b(b(b(?x_2))), a(a(c(?x_3))) = b(b(a(?x_3))), a(a(c(?x_7))) = b(b(c(?x_7))), a(c(a(c(?x_2)))) = c(b(b(b(?x_2)))), a(c(a(c(?x_3)))) = c(b(b(a(?x_3)))), a(c(a(c(?x_7)))) = c(b(b(c(?x_7)))), a(b(a(c(?x_2)))) = b(b(b(b(?x_2)))), a(b(a(c(?x_3)))) = b(b(b(a(?x_3)))), a(b(a(c(?x_7)))) = b(b(b(c(?x_7)))), a(c(c(?x))) = c(b(b(?x))), a(b(c(?x))) = b(b(b(?x))), c(a(b(?x_4))) = a(c(a(?x_4))), c(a(c(?x_5))) = a(c(b(?x_5))), b(b(a(b(?x_4)))) = a(a(c(a(?x_4)))), b(b(a(c(?x_5)))) = a(a(c(b(?x_5)))), a(c(a(b(?x_4)))) = c(a(c(a(?x_4)))), a(c(a(c(?x_5)))) = c(a(c(b(?x_5)))), b(b(b(?x))) = a(a(c(?x))), a(c(b(?x))) = c(a(c(?x))), c(b(b(?x_2))) = a(c(c(?x_2))), c(b(c(?x_6))) = a(c(b(?x_6))), b(b(b(b(?x_2)))) = a(a(c(c(?x_2)))), b(b(b(c(?x_6)))) = a(a(c(b(?x_6)))), a(c(b(b(?x_2)))) = c(a(c(c(?x_2)))), a(c(b(c(?x_6)))) = c(a(c(b(?x_6)))), b(b(a(?x))) = a(a(c(?x))), a(c(a(?x))) = c(a(c(?x))), b(b(b(?x_2))) = a(b(c(?x_2))), b(b(c(?x_6))) = a(b(b(?x_6))), a(c(b(b(?x_2)))) = c(a(b(c(?x_2)))), a(c(b(c(?x_6)))) = c(a(b(b(?x_6)))), a(c(b(b(?x_2)))) = b(a(b(c(?x_2)))), a(c(b(c(?x_6)))) = b(a(b(b(?x_6)))), b(c(b(b(?x_2)))) = a(a(b(c(?x_2)))), b(c(b(c(?x_6)))) = a(a(b(b(?x_6)))), a(c(a(?x))) = c(a(b(?x))), a(c(a(?x))) = b(a(b(?x))), b(c(a(?x))) = a(a(b(?x))), b(a(c(?x_1))) = a(c(b(?x_1))), b(a(b(?x_5))) = a(c(a(?x_5))), a(c(a(c(?x_1)))) = b(a(c(b(?x_1)))), a(c(a(b(?x_5)))) = b(a(c(a(?x_5)))), b(c(a(c(?x_1)))) = a(a(c(b(?x_1)))), b(c(a(b(?x_5)))) = a(a(c(a(?x_5)))), a(c(b(?x))) = b(a(c(?x))), b(c(b(?x))) = a(a(c(?x))), a(a(b(?x_5))) = b(c(a(?x_5))), a(a(c(?x_6))) = b(c(b(?x_6))), a(c(a(b(?x_5)))) = c(b(c(a(?x_5)))), a(c(a(c(?x_6)))) = c(b(c(b(?x_6)))), a(b(a(b(?x_5)))) = b(b(c(a(?x_5)))), a(b(a(c(?x_6)))) = b(b(c(b(?x_6)))), a(c(b(?x))) = c(b(c(?x))), a(b(b(?x))) = b(b(c(?x))), c(a(c(?x_1))) = a(c(c(?x_1))), c(a(c(?x_4))) = a(c(a(?x_4))), a(c(a(c(?x_1)))) = c(a(c(c(?x_1)))), a(c(a(c(?x_4)))) = c(a(c(a(?x_4)))), b(b(a(c(?x_1)))) = a(a(c(c(?x_1)))), b(b(a(c(?x_4)))) = a(a(c(a(?x_4)))), a(c(c(?x))) = c(a(c(?x))), b(b(c(?x))) = a(a(c(?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 [(a,1)] joinable by a reduction of rules <[], [([],4),([(a,1)],1)]> Critical Pair by Rules <2, 0> preceded by [(a,1)] joinable by a reduction of rules <[], [([],4),([(a,1)],2)]> joinable by a reduction of rules <[([(a,1)],0)], [([(b,1)],3),([],3)]> Critical Pair by Rules <6, 0> preceded by [(a,1)] joinable by a reduction of rules <[], [([],4),([(a,1)],6)]> Critical Pair by Rules <3, 1> preceded by [(c,1)] joinable by a reduction of rules <[([],2),([(a,1)],1)], [([(a,1)],2)]> Critical Pair by Rules <4, 1> preceded by [(c,1)] joinable by a reduction of rules <[([(c,1)],0),([],1)], []> joinable by a reduction of rules <[([],2),([(a,1)],6)], [([(a,1)],1)]> Critical Pair by Rules <0, 2> preceded by [(c,1)] joinable by a reduction of rules <[([(c,1)],4),([],2)], []> joinable by a reduction of rules <[([],1),([(a,1)],1)], [([(a,1)],6)]> Critical Pair by Rules <5, 2> preceded by [(c,1)] joinable by a reduction of rules <[([],1),([(a,1)],6)], [([(a,1)],1)]> Critical Pair by Rules <0, 3> preceded by [(b,1)] joinable by a reduction of rules <[([(b,1)],4),([],3)], []> joinable by a reduction of rules <[([(b,1)],4)], [([],5),([(b,1)],6)]> Critical Pair by Rules <5, 3> preceded by [(b,1)] joinable by a reduction of rules <[([],4),([(a,1)],6)], [([(a,1)],4)]> Critical Pair by Rules <3, 4> preceded by [(b,1)] joinable by a reduction of rules <[([],3),([(a,1)],4)], [([(a,1)],2)]> joinable by a reduction of rules <[], [([],0),([(b,1)],3)]> joinable by a reduction of rules <[([],3)], [([(a,1)],2),([(a,1)],0)]> Critical Pair by Rules <3, 5> preceded by [(a,1)] joinable by a reduction of rules <[([(a,1)],5)], [([(b,1)],2),([],3)]> Critical Pair by Rules <4, 5> preceded by [(a,1)] joinable by a reduction of rules <[([(a,1)],0),([],5)], []> Critical Pair by Rules <1, 6> preceded by [(c,1)] joinable by a reduction of rules <[([(c,1)],0),([],1)], []> joinable by a reduction of rules <[([],2),([(a,1)],6)], [([(a,1)],1)]> Critical Pair by Rules <2, 6> preceded by [(c,1)] joinable by a reduction of rules <[([],2),([(a,1)],6)], [([(a,1)],2)]> Critical Pair by Rules <4, 4> preceded by [(b,1)] joinable by a reduction of rules <[([(b,1)],0)], [([],0)]> Critical Pair by Rules <6, 6> preceded by [(c,1)] joinable by a reduction of rules <[([],2)], []> unknown Diagram Decreasing check Non-Confluence... obtain 11 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)), c(a(?x)) -> a(c(?x)), b(a(?x)) -> a(b(?x)), a(b(?x)) -> b(c(?x)), c(c(?x)) -> a(c(?x)) ] P: [ a(c(?x)) -> b(b(?x)), b(b(?x)) -> a(c(?x)) ] S: unknown termination failure(Step 1) STEP: 2 (linear) S: [ c(b(?x)) -> a(c(?x)), c(a(?x)) -> a(c(?x)), b(a(?x)) -> a(b(?x)), a(b(?x)) -> b(c(?x)), c(c(?x)) -> a(c(?x)) ] P: [ a(c(?x)) -> b(b(?x)), b(b(?x)) -> a(c(?x)) ] S: unknown termination failure(Step 2) STEP: 3 (relative) S: [ c(b(?x)) -> a(c(?x)), c(a(?x)) -> a(c(?x)), b(a(?x)) -> a(b(?x)), a(b(?x)) -> b(c(?x)), c(c(?x)) -> a(c(?x)) ] P: [ a(c(?x)) -> b(b(?x)), b(b(?x)) -> a(c(?x)) ] Check relative termination: [ c(b(?x)) -> a(c(?x)), c(a(?x)) -> a(c(?x)), b(a(?x)) -> a(b(?x)), a(b(?x)) -> b(c(?x)), c(c(?x)) -> a(c(?x)) ] [ a(c(?x)) -> b(b(?x)), b(b(?x)) -> a(c(?x)) ] Polynomial Interpretation: a:= (2)*x1 b:= (1)+(2)*x1 c:= (2)*x1 retract c(b(?x)) -> a(c(?x)) retract a(b(?x)) -> b(c(?x)) retract b(b(?x)) -> a(c(?x)) Polynomial Interpretation: a:= (9)+(2)*x1 b:= (2)+(2)*x1 c:= (3)*x1+(1)*x1*x1 retract c(b(?x)) -> a(c(?x)) retract c(a(?x)) -> a(c(?x)) retract a(b(?x)) -> b(c(?x)) retract a(c(?x)) -> b(b(?x)) retract b(b(?x)) -> a(c(?x)) Polynomial Interpretation: a:= (2)*x1 b:= (2)+(1)*x1*x1 c:= (1)+(2)*x1 retract c(b(?x)) -> a(c(?x)) retract c(a(?x)) -> a(c(?x)) retract a(b(?x)) -> b(c(?x)) retract c(c(?x)) -> a(c(?x)) retract a(c(?x)) -> b(b(?x)) retract b(b(?x)) -> a(c(?x)) Polynomial Interpretation: a:= (1)+(2)*x1 b:= (1)+(1)*x1+(2)*x1*x1 c:= (2)*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... [ a(c(?x)) -> b(b(?x)), c(b(?x)) -> a(c(?x)), c(a(?x)) -> a(c(?x)), b(a(?x)) -> a(b(?x)), b(b(?x)) -> a(c(?x)), a(b(?x)) -> b(c(?x)), c(c(?x)) -> a(c(?x)) ] Sort Assignment: a : 14=>14 b : 14=>14 c : 14=>14 maximal types: {14} Persistent Decomposition failed: Can't judge Try Layer Preserving Decomposition for... [ a(c(?x)) -> b(b(?x)), c(b(?x)) -> a(c(?x)), c(a(?x)) -> a(c(?x)), b(a(?x)) -> a(b(?x)), b(b(?x)) -> a(c(?x)), a(b(?x)) -> b(c(?x)), c(c(?x)) -> a(c(?x)) ] Layer Preserving Decomposition failed: Can't judge Try Commutative Decomposition for... [ a(c(?x)) -> b(b(?x)), c(b(?x)) -> a(c(?x)), c(a(?x)) -> a(c(?x)), b(a(?x)) -> a(b(?x)), b(b(?x)) -> a(c(?x)), a(b(?x)) -> b(c(?x)), c(c(?x)) -> a(c(?x)) ] Inside Critical Pair: by Rules <1, 0> develop reducts from lhs term... <{0}, a(b(b(?x_1)))> <{}, a(a(c(?x_1)))> develop reducts from rhs term... <{4}, a(c(b(?x_1)))> <{4}, b(a(c(?x_1)))> <{}, b(b(b(?x_1)))> Inside Critical Pair: by Rules <2, 0> develop reducts from lhs term... <{0}, a(b(b(?x_2)))> <{}, a(a(c(?x_2)))> develop reducts from rhs term... <{4}, a(c(a(?x_2)))> <{3}, b(a(b(?x_2)))> <{}, b(b(a(?x_2)))> Inside Critical Pair: by Rules <6, 0> develop reducts from lhs term... <{0}, a(b(b(?x_6)))> <{}, a(a(c(?x_6)))> develop reducts from rhs term... <{4}, a(c(c(?x_6)))> <{}, b(b(c(?x_6)))> Inside Critical Pair: by Rules <3, 1> develop reducts from lhs term... <{2}, a(c(b(?x_3)))> <{5}, c(b(c(?x_3)))> <{}, c(a(b(?x_3)))> develop reducts from rhs term... <{0}, b(b(a(?x_3)))> <{2}, a(a(c(?x_3)))> <{}, a(c(a(?x_3)))> Inside Critical Pair: by Rules <4, 1> develop reducts from lhs term... <{2}, a(c(c(?x_4)))> <{0}, c(b(b(?x_4)))> <{}, c(a(c(?x_4)))> develop reducts from rhs term... <{0}, b(b(b(?x_4)))> <{1}, a(a(c(?x_4)))> <{}, a(c(b(?x_4)))> Inside Critical Pair: by Rules <0, 2> develop reducts from lhs term... <{1}, a(c(b(?x)))> <{4}, c(a(c(?x)))> <{}, c(b(b(?x)))> develop reducts from rhs term... <{0}, b(b(c(?x)))> <{6}, a(a(c(?x)))> <{}, a(c(c(?x)))> Inside Critical Pair: by Rules <5, 2> develop reducts from lhs term... <{1}, a(c(c(?x_5)))> <{}, c(b(c(?x_5)))> develop reducts from rhs term... <{0}, b(b(b(?x_5)))> <{1}, a(a(c(?x_5)))> <{}, a(c(b(?x_5)))> Inside Critical Pair: by Rules <0, 3> develop reducts from lhs term... <{4}, a(c(b(?x)))> <{4}, b(a(c(?x)))> <{}, b(b(b(?x)))> develop reducts from rhs term... <{5}, b(c(c(?x)))> <{}, a(b(c(?x)))> Inside Critical Pair: by Rules <5, 3> develop reducts from lhs term... <{4}, a(c(c(?x_5)))> <{}, b(b(c(?x_5)))> develop reducts from rhs term... <{5}, b(c(b(?x_5)))> <{4}, a(a(c(?x_5)))> <{}, a(b(b(?x_5)))> Inside Critical Pair: by Rules <3, 4> develop reducts from lhs term... <{3}, a(b(b(?x_3)))> <{5}, b(b(c(?x_3)))> <{}, b(a(b(?x_3)))> develop reducts from rhs term... <{0}, b(b(a(?x_3)))> <{2}, a(a(c(?x_3)))> <{}, a(c(a(?x_3)))> Inside Critical Pair: by Rules <3, 5> develop reducts from lhs term... <{5}, a(b(c(?x_3)))> <{}, a(a(b(?x_3)))> develop reducts from rhs term... <{2}, b(a(c(?x_3)))> <{}, b(c(a(?x_3)))> Inside Critical Pair: by Rules <4, 5> develop reducts from lhs term... <{0}, a(b(b(?x_4)))> <{}, a(a(c(?x_4)))> develop reducts from rhs term... <{1}, b(a(c(?x_4)))> <{}, b(c(b(?x_4)))> Inside Critical Pair: by Rules <1, 6> develop reducts from lhs term... <{2}, a(c(c(?x_1)))> <{0}, c(b(b(?x_1)))> <{}, c(a(c(?x_1)))> develop reducts from rhs term... <{0}, b(b(b(?x_1)))> <{1}, a(a(c(?x_1)))> <{}, a(c(b(?x_1)))> Inside Critical Pair: by Rules <2, 6> develop reducts from lhs term... <{2}, a(c(c(?x_2)))> <{0}, c(b(b(?x_2)))> <{}, c(a(c(?x_2)))> develop reducts from rhs term... <{0}, b(b(a(?x_2)))> <{2}, a(a(c(?x_2)))> <{}, a(c(a(?x_2)))> Commutative Decomposition failed: Can't judge No further decomposition possible Combined result: Can't judge 993.trs: Failure(unknown CR) MAYBE (5814 msec.)