(ignored inputs)COMMENT submitted by: Johannes Waldmann Rewrite Rules: [ a(c(?x)) -> b(c(?x)), a(b(?x)) -> c(c(?x)), a(a(?x)) -> c(c(?x)), a(b(?x)) -> c(a(?x)), b(b(?x)) -> a(a(?x)), c(b(?x)) -> c(a(?x)), c(c(?x)) -> a(b(?x)), c(b(?x)) -> c(c(?x)), b(c(?x)) -> a(c(?x)) ] Apply Direct Methods... Inner CPs: [ a(c(a(?x_5))) = b(c(b(?x_5))), a(a(b(?x_6))) = b(c(c(?x_6))), a(c(c(?x_7))) = b(c(b(?x_7))), a(a(a(?x_4))) = c(c(b(?x_4))), a(a(c(?x_8))) = c(c(c(?x_8))), a(b(c(?x))) = c(c(c(?x))), a(c(c(?x_1))) = c(c(b(?x_1))), a(c(a(?x_3))) = c(c(b(?x_3))), a(a(a(?x_4))) = c(a(b(?x_4))), a(a(c(?x_8))) = c(a(c(?x_8))), b(a(c(?x_8))) = a(a(c(?x_8))), c(a(a(?x_4))) = c(a(b(?x_4))), c(a(c(?x_8))) = c(a(c(?x_8))), c(c(a(?x_5))) = a(b(b(?x_5))), c(c(c(?x_7))) = a(b(b(?x_7))), c(a(a(?x_4))) = c(c(b(?x_4))), c(a(c(?x_8))) = c(c(c(?x_8))), b(c(a(?x_5))) = a(c(b(?x_5))), b(a(b(?x_6))) = a(c(c(?x_6))), b(c(c(?x_7))) = a(c(b(?x_7))), a(c(c(?x))) = c(c(a(?x))), b(a(a(?x))) = a(a(b(?x))), c(a(b(?x))) = a(b(c(?x))) ] Outer CPs: [ c(c(?x_1)) = c(a(?x_1)), c(a(?x_5)) = c(c(?x_5)) ] 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: [ a(c(a(?x_6))) = b(c(b(?x_6))), a(a(b(?x_7))) = b(c(c(?x_7))), a(c(c(?x_8))) = b(c(b(?x_8))), c(c(c(a(?x_6)))) = a(b(c(b(?x_6)))), c(c(a(b(?x_7)))) = a(b(c(c(?x_7)))), c(c(c(c(?x_8)))) = a(b(c(b(?x_8)))), c(c(c(?x))) = a(b(c(?x))), c(a(?x)) = c(c(?x)), a(a(a(?x_5))) = c(c(b(?x_5))), a(a(c(?x_9))) = c(c(c(?x_9))), c(c(a(a(?x_5)))) = a(c(c(b(?x_5)))), c(c(a(c(?x_9)))) = a(c(c(c(?x_9)))), c(c(b(?x))) = a(c(c(?x))), a(c(c(?x_1))) = c(c(a(?x_1))), a(b(c(?x_2))) = c(c(c(?x_2))), a(c(c(?x_3))) = c(c(b(?x_3))), a(c(a(?x_4))) = c(c(b(?x_4))), c(c(c(c(?x_1)))) = a(c(c(a(?x_1)))), c(c(b(c(?x_2)))) = a(c(c(c(?x_2)))), c(c(c(c(?x_3)))) = a(c(c(b(?x_3)))), c(c(c(a(?x_4)))) = a(c(c(b(?x_4)))), c(c(a(?x))) = a(c(c(?x))), c(c(?x)) = c(a(?x)), a(a(a(?x_5))) = c(a(b(?x_5))), a(a(c(?x_9))) = c(a(c(?x_9))), c(c(a(a(?x_5)))) = a(c(a(b(?x_5)))), c(c(a(c(?x_9)))) = a(c(a(c(?x_9)))), c(c(b(?x))) = a(c(a(?x))), b(a(a(?x_1))) = a(a(b(?x_1))), b(a(c(?x_9))) = a(a(c(?x_9))), a(a(a(a(?x_1)))) = b(a(a(b(?x_1)))), a(a(a(c(?x_9)))) = b(a(a(c(?x_9)))), c(c(a(a(?x_1)))) = a(a(a(b(?x_1)))), c(c(a(c(?x_9)))) = a(a(a(c(?x_9)))), c(a(a(a(?x_1)))) = a(a(a(b(?x_1)))), c(a(a(c(?x_9)))) = a(a(a(c(?x_9)))), c(a(a(a(?x_1)))) = c(a(a(b(?x_1)))), c(a(a(c(?x_9)))) = c(a(a(c(?x_9)))), c(c(a(a(?x_1)))) = c(a(a(b(?x_1)))), c(c(a(c(?x_9)))) = c(a(a(c(?x_9)))), a(a(b(?x))) = b(a(a(?x))), c(c(b(?x))) = a(a(a(?x))), c(a(b(?x))) = a(a(a(?x))), c(a(b(?x))) = c(a(a(?x))), c(c(b(?x))) = c(a(a(?x))), c(a(a(?x_6))) = c(a(b(?x_6))), c(a(c(?x_9))) = c(a(c(?x_9))), b(c(a(a(?x_6)))) = a(c(a(b(?x_6)))), b(c(a(c(?x_9)))) = a(c(a(c(?x_9)))), a(b(a(a(?x_6)))) = c(c(a(b(?x_6)))), a(b(a(c(?x_9)))) = c(c(a(c(?x_9)))), a(c(a(a(?x_6)))) = b(c(a(b(?x_6)))), a(c(a(c(?x_9)))) = b(c(a(c(?x_9)))), b(c(b(?x))) = a(c(a(?x))), a(b(b(?x))) = c(c(a(?x))), a(c(b(?x))) = b(c(a(?x))), c(a(b(?x_1))) = a(b(c(?x_1))), c(c(a(?x_7))) = a(b(b(?x_7))), c(c(c(?x_8))) = a(b(b(?x_8))), a(b(a(b(?x_1)))) = c(a(b(c(?x_1)))), a(b(c(a(?x_7)))) = c(a(b(b(?x_7)))), a(b(c(c(?x_8)))) = c(a(b(b(?x_8)))), b(c(a(b(?x_1)))) = a(a(b(c(?x_1)))), b(c(c(a(?x_7)))) = a(a(b(b(?x_7)))), b(c(c(c(?x_8)))) = a(a(b(b(?x_8)))), a(c(a(b(?x_1)))) = b(a(b(c(?x_1)))), a(c(c(a(?x_7)))) = b(a(b(b(?x_7)))), a(c(c(c(?x_8)))) = b(a(b(b(?x_8)))), a(b(c(?x))) = c(a(b(?x))), b(c(c(?x))) = a(a(b(?x))), a(c(c(?x))) = b(a(b(?x))), c(a(a(?x_6))) = c(c(b(?x_6))), c(a(c(?x_9))) = c(c(c(?x_9))), b(c(a(a(?x_6)))) = a(c(c(b(?x_6)))), b(c(a(c(?x_9)))) = a(c(c(c(?x_9)))), a(b(a(a(?x_6)))) = c(c(c(b(?x_6)))), a(b(a(c(?x_9)))) = c(c(c(c(?x_9)))), a(c(a(a(?x_6)))) = b(c(c(b(?x_6)))), a(c(a(c(?x_9)))) = b(c(c(c(?x_9)))), b(c(b(?x))) = a(c(c(?x))), a(b(b(?x))) = c(c(c(?x))), a(c(b(?x))) = b(c(c(?x))), b(c(a(?x_7))) = a(c(b(?x_7))), b(a(b(?x_8))) = a(c(c(?x_8))), b(c(c(?x_9))) = a(c(b(?x_9))), c(c(c(a(?x_7)))) = a(a(c(b(?x_7)))), c(c(a(b(?x_8)))) = a(a(c(c(?x_8)))), c(c(c(c(?x_9)))) = a(a(c(b(?x_9)))), c(a(c(a(?x_7)))) = a(a(c(b(?x_7)))), c(a(a(b(?x_8)))) = a(a(c(c(?x_8)))), c(a(c(c(?x_9)))) = a(a(c(b(?x_9)))), a(a(c(a(?x_7)))) = b(a(c(b(?x_7)))), a(a(a(b(?x_8)))) = b(a(c(c(?x_8)))), a(a(c(c(?x_9)))) = b(a(c(b(?x_9)))), c(a(c(a(?x_7)))) = c(a(c(b(?x_7)))), c(a(a(b(?x_8)))) = c(a(c(c(?x_8)))), c(a(c(c(?x_9)))) = c(a(c(b(?x_9)))), c(c(c(a(?x_7)))) = c(a(c(b(?x_7)))), c(c(a(b(?x_8)))) = c(a(c(c(?x_8)))), c(c(c(c(?x_9)))) = c(a(c(b(?x_9)))), c(c(c(?x))) = a(a(c(?x))), c(a(c(?x))) = a(a(c(?x))), a(a(c(?x))) = b(a(c(?x))), c(c(c(?x))) = c(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 <5, 0> preceded by [(a,1)] joinable by a reduction of rules <[([],0)], [([(b,1)],5)]> Critical Pair by Rules <6, 0> preceded by [(a,1)] joinable by a reduction of rules <[([(a,1)],1)], [([],8)]> Critical Pair by Rules <7, 0> preceded by [(a,1)] joinable by a reduction of rules <[([],0)], [([(b,1)],7)]> Critical Pair by Rules <4, 1> preceded by [(a,1)] joinable by a reduction of rules <[([],2)], [([(c,1)],5)]> Critical Pair by Rules <8, 1> preceded by [(a,1)] joinable by a reduction of rules <[([],2)], []> joinable by a reduction of rules <[([(a,1)],0)], [([],6)]> Critical Pair by Rules <0, 2> preceded by [(a,1)] joinable by a reduction of rules <[([],1)], []> joinable by a reduction of rules <[], [([],6)]> Critical Pair by Rules <1, 2> preceded by [(a,1)] joinable by a reduction of rules <[([(a,1)],6),([],2)], []> Critical Pair by Rules <3, 2> preceded by [(a,1)] joinable by a reduction of rules <[], [([],6),([(a,1)],4),([(a,1)],2),([(a,1)],6),([(a,1)],3)]> Critical Pair by Rules <4, 3> preceded by [(a,1)] joinable by a reduction of rules <[([],2)], [([(c,1)],3)]> Critical Pair by Rules <8, 3> preceded by [(a,1)] joinable by a reduction of rules <[([(a,1)],0),([],3)], []> joinable by a reduction of rules <[([],2)], [([(c,1)],0),([],7)]> joinable by a reduction of rules <[([(a,1)],0),([],1)], [([(c,1)],0),([],7)]> Critical Pair by Rules <8, 4> preceded by [(b,1)] joinable by a reduction of rules <[([(b,1)],0),([],4)], []> Critical Pair by Rules <4, 5> preceded by [(c,1)] joinable by a reduction of rules <[([(c,1)],2)], [([(c,1)],1)]> Critical Pair by Rules <8, 5> preceded by [(c,1)] joinable by a reduction of rules <[], []> Critical Pair by Rules <5, 6> preceded by [(c,1)] joinable by a reduction of rules <[], [([(a,1)],4),([],2)]> joinable by a reduction of rules <[], [([],3),([(c,1)],3)]> joinable by a reduction of rules <[], [([],1),([(c,1)],5)]> Critical Pair by Rules <7, 6> preceded by [(c,1)] joinable by a reduction of rules <[([(c,1)],6)], [([],3)]> Critical Pair by Rules <4, 7> preceded by [(c,1)] joinable by a reduction of rules <[([(c,1)],2)], [([(c,1)],7)]> Critical Pair by Rules <8, 7> preceded by [(c,1)] joinable by a reduction of rules <[([(c,1)],0),([],7)], []> joinable by a reduction of rules <[], [([],6),([],3)]> Critical Pair by Rules <5, 8> preceded by [(b,1)] joinable by a reduction of rules <[([],8)], [([(a,1)],5)]> Critical Pair by Rules <6, 8> preceded by [(b,1)] joinable by a reduction of rules <[([(b,1)],1)], [([],0)]> Critical Pair by Rules <7, 8> preceded by [(b,1)] joinable by a reduction of rules <[([],8)], [([(a,1)],7)]> Critical Pair by Rules <2, 2> preceded by [(a,1)] joinable by a reduction of rules <[([(a,1)],6),([],2),([(c,1)],5)], []> joinable by a reduction of rules <[([(a,1)],6),([],2),([(c,1)],7)], [([],6),([],3),([(c,1)],2)]> Critical Pair by Rules <4, 4> preceded by [(b,1)] joinable by a reduction of rules <[([(b,1)],2),([],8)], [([(a,1)],1)]> joinable by a reduction of rules <[([(b,1)],2)], [([(a,1)],1),([],0)]> Critical Pair by Rules <6, 6> preceded by [(c,1)] joinable by a reduction of rules <[([(c,1)],1)], [([],1)]> Critical Pair by Rules <3, 1> preceded by [] joinable by a reduction of rules <[], [([],6),([],3)]> Critical Pair by Rules <7, 5> preceded by [] joinable by a reduction of rules <[([],6),([],3)], []> unknown Diagram Decreasing check Non-Confluence... obtain 14 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: [ a(a(?x)) -> c(c(?x)), a(b(?x)) -> c(a(?x)), b(b(?x)) -> a(a(?x)), c(b(?x)) -> c(a(?x)), c(b(?x)) -> c(c(?x)) ] P: [ a(c(?x)) -> b(c(?x)), a(b(?x)) -> c(c(?x)), c(c(?x)) -> a(b(?x)), b(c(?x)) -> a(c(?x)) ] S: terminating CP(S,S): --> => no --> => no --> => no --> => no --> => no --> => no --> => no --> => no PCP_in(symP,S): --> => no --> => no --> => no --> => no --> => yes --> => no CP(S,symP): --> => no --> => no --> => yes --> => no --> => yes --> => no --> => no --> => no check joinability condition: check modulo joinability of a(c(c(?x))) and c(c(a(?x))): maybe not joinable check modulo joinability of a(c(a(?x_1))) and c(c(a(?x_1))): maybe not joinable check modulo joinability of a(c(c(?x_2))) and c(c(a(?x_2))): maybe not joinable check modulo joinability of b(c(c(?x))) and a(c(a(?x))): joinable by {1} check modulo joinability of c(c(c(?x_2))) and c(c(a(?x_2))): joinable by {1} check modulo joinability of c(c(?x_4)) and c(a(?x_4)): joinable by {1} check modulo joinability of c(c(c(?x_2))) and c(c(a(?x_2))): joinable by {1} check modulo joinability of c(a(?x_3)) and c(c(?x_3)): joinable by {1} check modulo joinability of c(a(c(?x_4))) and c(c(c(?x_4))): joinable by {1} check modulo reachablity from c(c(a(?x_3))) to a(c(c(?x_3))): maybe not reachable check modulo joinability of c(c(c(?x_1))) and c(a(c(?x_1))): joinable by {1} check modulo reachablity from c(c(c(?x_1))) to b(a(c(?x_1))): maybe not reachable check modulo reachablity from c(c(c(?x_1))) to c(a(c(?x_1))): reachable by {1} check modulo reachablity from c(a(?x)) to c(c(?x)): maybe not reachable check modulo joinability of a(c(c(?x))) and c(c(a(?x))): maybe not joinable check modulo joinability of c(c(a(?x))) and a(c(c(?x))): maybe not joinable check modulo joinability of b(c(c(?x))) and a(c(a(?x))): joinable by {1} check modulo joinability of c(c(c(?x))) and a(c(c(?x))): maybe not joinable check modulo joinability of a(c(c(?x))) and b(c(a(?x))): joinable by {0,1} failed failure(Step 1) [ c(c(?x)) -> c(a(?x)) ] Added S-Rules: [ c(c(?x)) -> c(a(?x)) ] Added P-Rules: [ ] replace: c(b(?x)) -> c(c(?x)) => c(b(?x)) -> a(b(?x)) STEP: 2 (linear) S: [ a(a(?x)) -> c(c(?x)), a(b(?x)) -> c(a(?x)), b(b(?x)) -> a(a(?x)), c(b(?x)) -> c(a(?x)), c(b(?x)) -> c(c(?x)) ] P: [ a(c(?x)) -> b(c(?x)), a(b(?x)) -> c(c(?x)), c(c(?x)) -> a(b(?x)), b(c(?x)) -> a(c(?x)) ] S: terminating CP(S,S): --> => no --> => no --> => no --> => no --> => no --> => no --> => no --> => no CP_in(symP,S): --> => no --> => no --> => yes --> => no --> => no --> => no CP(S,symP): --> => no --> => no --> => yes --> => no --> => yes --> => no --> => no --> => no check joinability condition: check modulo joinability of a(c(c(?x))) and c(c(a(?x))): maybe not joinable check modulo joinability of a(c(a(?x_1))) and c(c(a(?x_1))): maybe not joinable check modulo joinability of a(c(c(?x_2))) and c(c(a(?x_2))): maybe not joinable check modulo joinability of b(c(c(?x))) and a(c(a(?x))): joinable by {1} check modulo joinability of c(c(c(?x_2))) and c(c(a(?x_2))): joinable by {1} check modulo joinability of c(c(?x_4)) and c(a(?x_4)): maybe not joinable check modulo joinability of c(c(c(?x_2))) and c(c(a(?x_2))): joinable by {1} check modulo joinability of c(a(?x_3)) and c(c(?x_3)): maybe not joinable check modulo joinability of c(c(c(?x))) and c(a(c(?x))): joinable by {1,3} check modulo reachablity from c(c(c(?x))) to b(a(c(?x))): maybe not reachable check modulo reachablity from c(c(c(?x))) to c(a(c(?x))): reachable by {1,3} check modulo reachablity from c(c(a(?x))) to a(c(c(?x))): maybe not reachable check modulo joinability of c(a(c(?x))) and c(c(c(?x))): joinable by {1,3} check modulo reachablity from c(a(?x)) to c(c(?x)): maybe not reachable check modulo joinability of a(c(c(?x))) and c(c(a(?x))): maybe not joinable check modulo joinability of c(c(a(?x))) and a(c(c(?x))): maybe not joinable check modulo joinability of b(c(c(?x))) and a(c(a(?x))): joinable by {1} check modulo joinability of c(c(c(?x))) and a(c(c(?x))): maybe not joinable check modulo joinability of a(c(c(?x))) and b(c(a(?x))): joinable by {1} failed failure(Step 2) [ c(c(?x)) -> c(a(?x)) ] Added S-Rules: [ c(c(?x)) -> c(a(?x)) ] Added P-Rules: [ ] replace: c(b(?x)) -> c(c(?x)) => c(b(?x)) -> a(b(?x)) STEP: 3 (relative) S: [ a(a(?x)) -> c(c(?x)), a(b(?x)) -> c(a(?x)), b(b(?x)) -> a(a(?x)), c(b(?x)) -> c(a(?x)), c(b(?x)) -> c(c(?x)) ] P: [ a(c(?x)) -> b(c(?x)), a(b(?x)) -> c(c(?x)), c(c(?x)) -> a(b(?x)), b(c(?x)) -> a(c(?x)) ] Check relative termination: [ a(a(?x)) -> c(c(?x)), a(b(?x)) -> c(a(?x)), b(b(?x)) -> a(a(?x)), c(b(?x)) -> c(a(?x)), c(b(?x)) -> c(c(?x)) ] [ a(c(?x)) -> b(c(?x)), a(b(?x)) -> c(c(?x)), c(c(?x)) -> a(b(?x)), b(c(?x)) -> a(c(?x)) ] Polynomial Interpretation: a:= (1)*x1 b:= (4)+(1)*x1 c:= (1)*x1 retract a(b(?x)) -> c(a(?x)) retract b(b(?x)) -> a(a(?x)) retract c(b(?x)) -> c(a(?x)) retract c(b(?x)) -> c(c(?x)) retract a(b(?x)) -> c(c(?x)) retract b(c(?x)) -> a(c(?x)) Polynomial Interpretation: a:= (2)+(2)*x1+(1)*x1*x1 b:= (1)+(1)*x1*x1 c:= (2)+(1)*x1+(1)*x1*x1 relatively terminating S/P: relatively terminating check CP condition: failed failure(Step 3) STEP: 4 (parallel) S: [ a(a(?x)) -> c(c(?x)), a(b(?x)) -> c(a(?x)), b(b(?x)) -> a(a(?x)), c(b(?x)) -> c(a(?x)), c(b(?x)) -> c(c(?x)), c(c(?x)) -> c(a(?x)) ] P: [ a(c(?x)) -> b(c(?x)), a(b(?x)) -> c(c(?x)), c(c(?x)) -> a(b(?x)), b(c(?x)) -> a(c(?x)) ] S: unknown termination failure(Step 4) STEP: 5 (linear) S: [ a(a(?x)) -> c(c(?x)), a(b(?x)) -> c(a(?x)), b(b(?x)) -> a(a(?x)), c(b(?x)) -> c(a(?x)), c(b(?x)) -> c(c(?x)), c(c(?x)) -> c(a(?x)) ] P: [ a(c(?x)) -> b(c(?x)), a(b(?x)) -> c(c(?x)), c(c(?x)) -> a(b(?x)), b(c(?x)) -> a(c(?x)) ] S: unknown termination failure(Step 5) STEP: 6 (relative) S: [ a(a(?x)) -> c(c(?x)), a(b(?x)) -> c(a(?x)), b(b(?x)) -> a(a(?x)), c(b(?x)) -> c(a(?x)), c(b(?x)) -> c(c(?x)), c(c(?x)) -> c(a(?x)) ] P: [ a(c(?x)) -> b(c(?x)), a(b(?x)) -> c(c(?x)), c(c(?x)) -> a(b(?x)), b(c(?x)) -> a(c(?x)) ] Check relative termination: [ a(a(?x)) -> c(c(?x)), a(b(?x)) -> c(a(?x)), b(b(?x)) -> a(a(?x)), c(b(?x)) -> c(a(?x)), c(b(?x)) -> c(c(?x)), c(c(?x)) -> c(a(?x)) ] [ a(c(?x)) -> b(c(?x)), a(b(?x)) -> c(c(?x)), c(c(?x)) -> a(b(?x)), b(c(?x)) -> a(c(?x)) ] Polynomial Interpretation: a:= (3)*x1 b:= (3)+(3)*x1 c:= (3)*x1 retract a(b(?x)) -> c(a(?x)) retract b(b(?x)) -> a(a(?x)) retract c(b(?x)) -> c(a(?x)) retract c(b(?x)) -> c(c(?x)) retract a(b(?x)) -> c(c(?x)) retract b(c(?x)) -> a(c(?x)) Polynomial Interpretation: a:= (1)+(3)*x1 b:= (3)+(1)*x1 c:= (3)*x1 retract a(a(?x)) -> c(c(?x)) retract a(b(?x)) -> c(a(?x)) retract b(b(?x)) -> a(a(?x)) retract c(b(?x)) -> c(a(?x)) retract c(b(?x)) -> c(c(?x)) retract a(b(?x)) -> c(c(?x)) retract b(c(?x)) -> a(c(?x)) Polynomial Interpretation: a:= (3)*x1 b:= (3)+(1)*x1 c:= (1)+(3)*x1 relatively terminating S/P: relatively terminating check CP condition: failed failure(Step 6) STEP: 7 (parallel) S: [ a(a(?x)) -> c(c(?x)), a(b(?x)) -> c(a(?x)), b(b(?x)) -> a(a(?x)), c(b(?x)) -> c(a(?x)), c(b(?x)) -> a(b(?x)) ] P: [ a(c(?x)) -> b(c(?x)), a(b(?x)) -> c(c(?x)), c(c(?x)) -> a(b(?x)), b(c(?x)) -> a(c(?x)) ] S: terminating CP(S,S): --> => no --> => no --> => no --> => no --> => no --> => yes --> => no --> => yes PCP_in(symP,S): --> => no --> => no --> => no --> => no --> => yes --> => yes CP(S,symP): --> => no --> => no --> => yes --> => no --> => yes --> => yes --> => no --> => yes check joinability condition: check modulo joinability of a(c(c(?x))) and c(c(a(?x))): maybe not joinable check modulo joinability of a(c(a(?x_1))) and c(c(a(?x_1))): maybe not joinable check modulo joinability of a(c(c(?x_2))) and c(c(a(?x_2))): maybe not joinable check modulo joinability of b(c(c(?x))) and a(c(a(?x))): joinable by {1} check modulo joinability of c(c(c(?x_2))) and c(c(a(?x_2))): joinable by {1} check modulo joinability of c(c(c(?x_2))) and a(c(c(?x_2))): maybe not joinable check modulo joinability of c(a(c(?x_4))) and c(c(c(?x_4))): joinable by {1} check modulo reachablity from c(c(a(?x_3))) to a(c(c(?x_3))): maybe not reachable check modulo joinability of c(c(c(?x_1))) and c(a(c(?x_1))): joinable by {1} check modulo reachablity from c(c(c(?x_1))) to b(a(c(?x_1))): maybe not reachable check modulo reachablity from c(a(?x)) to c(c(?x)): maybe not reachable check modulo joinability of a(c(c(?x))) and c(c(a(?x))): maybe not joinable check modulo joinability of c(c(a(?x))) and a(c(c(?x))): maybe not joinable check modulo joinability of c(c(a(?x))) and a(c(c(?x))): maybe not joinable failed failure(Step 7) [ c(c(?x)) -> c(a(?x)) ] Added S-Rules: [ c(c(?x)) -> c(a(?x)) ] Added P-Rules: [ ] replace: c(b(?x)) -> a(b(?x)) => c(b(?x)) -> c(c(?x)) STEP: 8 (linear) S: [ a(a(?x)) -> c(c(?x)), a(b(?x)) -> c(a(?x)), b(b(?x)) -> a(a(?x)), c(b(?x)) -> c(a(?x)), c(b(?x)) -> a(b(?x)) ] P: [ a(c(?x)) -> b(c(?x)), a(b(?x)) -> c(c(?x)), c(c(?x)) -> a(b(?x)), b(c(?x)) -> a(c(?x)) ] S: terminating CP(S,S): --> => no --> => no --> => no --> => no --> => no --> => yes --> => no --> => yes CP_in(symP,S): --> => no --> => no --> => yes --> => yes --> => no --> => no CP(S,symP): --> => no --> => no --> => yes --> => no --> => yes --> => yes --> => no --> => yes check joinability condition: check modulo joinability of a(c(c(?x))) and c(c(a(?x))): maybe not joinable check modulo joinability of a(c(a(?x_1))) and c(c(a(?x_1))): maybe not joinable check modulo joinability of a(c(c(?x_2))) and c(c(a(?x_2))): maybe not joinable check modulo joinability of b(c(c(?x))) and a(c(a(?x))): joinable by {1} check modulo joinability of c(c(c(?x_2))) and c(c(a(?x_2))): joinable by {1} check modulo joinability of c(c(c(?x_2))) and a(c(c(?x_2))): maybe not joinable check modulo joinability of c(c(c(?x))) and c(a(c(?x))): joinable by {1,3} check modulo reachablity from c(c(c(?x))) to b(a(c(?x))): maybe not reachable check modulo reachablity from c(c(a(?x))) to a(c(c(?x))): maybe not reachable check modulo joinability of c(a(c(?x))) and c(c(c(?x))): joinable by {1,3} check modulo reachablity from c(a(?x)) to c(c(?x)): maybe not reachable check modulo joinability of a(c(c(?x))) and c(c(a(?x))): maybe not joinable check modulo joinability of c(c(a(?x))) and a(c(c(?x))): maybe not joinable check modulo joinability of c(c(a(?x))) and a(c(c(?x))): maybe not joinable failed failure(Step 8) [ c(c(?x)) -> c(a(?x)) ] Added S-Rules: [ c(c(?x)) -> c(a(?x)) ] Added P-Rules: [ ] replace: c(b(?x)) -> a(b(?x)) => c(b(?x)) -> c(c(?x)) STEP: 9 (relative) S: [ a(a(?x)) -> c(c(?x)), a(b(?x)) -> c(a(?x)), b(b(?x)) -> a(a(?x)), c(b(?x)) -> c(a(?x)), c(b(?x)) -> a(b(?x)) ] P: [ a(c(?x)) -> b(c(?x)), a(b(?x)) -> c(c(?x)), c(c(?x)) -> a(b(?x)), b(c(?x)) -> a(c(?x)) ] Check relative termination: [ a(a(?x)) -> c(c(?x)), a(b(?x)) -> c(a(?x)), b(b(?x)) -> a(a(?x)), c(b(?x)) -> c(a(?x)), c(b(?x)) -> a(b(?x)) ] [ a(c(?x)) -> b(c(?x)), a(b(?x)) -> c(c(?x)), c(c(?x)) -> a(b(?x)), b(c(?x)) -> a(c(?x)) ] Polynomial Interpretation: a:= (1)*x1 b:= (1)*x1 c:= (2)+(1)*x1 retract c(b(?x)) -> a(b(?x)) retract c(c(?x)) -> a(b(?x)) Polynomial Interpretation: a:= (1)*x1 b:= (8)+(1)*x1 c:= (1)*x1 retract a(b(?x)) -> c(a(?x)) retract c(b(?x)) -> c(a(?x)) retract c(b(?x)) -> a(b(?x)) retract a(b(?x)) -> c(c(?x)) retract c(c(?x)) -> a(b(?x)) retract b(c(?x)) -> a(c(?x)) Polynomial Interpretation: a:= (1)*x1*x1 b:= (1)+(1)*x1*x1 c:= (1)*x1*x1 retract a(b(?x)) -> c(a(?x)) retract b(b(?x)) -> a(a(?x)) retract c(b(?x)) -> c(a(?x)) retract c(b(?x)) -> a(b(?x)) retract a(b(?x)) -> c(c(?x)) retract c(c(?x)) -> a(b(?x)) retract b(c(?x)) -> a(c(?x)) Polynomial Interpretation: a:= (3)+(1)*x1+(1)*x1*x1 b:= (1)+(2)*x1 c:= (2)+(1)*x1+(1)*x1*x1 relatively terminating S/P: relatively terminating check CP condition: failed failure(Step 9) STEP: 10 (parallel) S: [ a(a(?x)) -> c(c(?x)), a(b(?x)) -> c(a(?x)), b(b(?x)) -> a(a(?x)), c(b(?x)) -> c(a(?x)), c(b(?x)) -> a(b(?x)), c(c(?x)) -> c(a(?x)) ] P: [ a(c(?x)) -> b(c(?x)), a(b(?x)) -> c(c(?x)), c(c(?x)) -> a(b(?x)), b(c(?x)) -> a(c(?x)) ] S: unknown termination failure(Step 10) STEP: 11 (linear) S: [ a(a(?x)) -> c(c(?x)), a(b(?x)) -> c(a(?x)), b(b(?x)) -> a(a(?x)), c(b(?x)) -> c(a(?x)), c(b(?x)) -> a(b(?x)), c(c(?x)) -> c(a(?x)) ] P: [ a(c(?x)) -> b(c(?x)), a(b(?x)) -> c(c(?x)), c(c(?x)) -> a(b(?x)), b(c(?x)) -> a(c(?x)) ] S: unknown termination failure(Step 11) STEP: 12 (relative) S: [ a(a(?x)) -> c(c(?x)), a(b(?x)) -> c(a(?x)), b(b(?x)) -> a(a(?x)), c(b(?x)) -> c(a(?x)), c(b(?x)) -> a(b(?x)), c(c(?x)) -> c(a(?x)) ] P: [ a(c(?x)) -> b(c(?x)), a(b(?x)) -> c(c(?x)), c(c(?x)) -> a(b(?x)), b(c(?x)) -> a(c(?x)) ] Check relative termination: [ a(a(?x)) -> c(c(?x)), a(b(?x)) -> c(a(?x)), b(b(?x)) -> a(a(?x)), c(b(?x)) -> c(a(?x)), c(b(?x)) -> a(b(?x)), c(c(?x)) -> c(a(?x)) ] [ a(c(?x)) -> b(c(?x)), a(b(?x)) -> c(c(?x)), c(c(?x)) -> a(b(?x)), b(c(?x)) -> a(c(?x)) ] Polynomial Interpretation: a:= (2)+(1)*x1 b:= (1)*x1 c:= (1)*x1 retract a(a(?x)) -> c(c(?x)) retract a(c(?x)) -> b(c(?x)) retract a(b(?x)) -> c(c(?x)) Polynomial Interpretation: a:= (1)*x1*x1 b:= (2)+(1)*x1*x1 c:= (2)*x1+(1)*x1*x1 retract a(a(?x)) -> c(c(?x)) retract a(b(?x)) -> c(a(?x)) retract b(b(?x)) -> a(a(?x)) retract c(b(?x)) -> c(a(?x)) retract c(b(?x)) -> a(b(?x)) retract a(c(?x)) -> b(c(?x)) retract a(b(?x)) -> c(c(?x)) retract b(c(?x)) -> a(c(?x)) Polynomial Interpretation: a:= (1)*x1 b:= (2)*x1*x1 c:= (1)+(1)*x1*x1 relatively terminating S/P: relatively terminating check CP condition: failed failure(Step 12) failure(no possibility remains) unknown Reduction-Preserving Completion Direct Methods: Can't judge Try Persistent Decomposition for... [ a(c(?x)) -> b(c(?x)), a(b(?x)) -> c(c(?x)), a(a(?x)) -> c(c(?x)), a(b(?x)) -> c(a(?x)), b(b(?x)) -> a(a(?x)), c(b(?x)) -> c(a(?x)), c(c(?x)) -> a(b(?x)), c(b(?x)) -> c(c(?x)), b(c(?x)) -> a(c(?x)) ] Sort Assignment: a : 16=>16 b : 16=>16 c : 16=>16 maximal types: {16} Persistent Decomposition failed: Can't judge Try Layer Preserving Decomposition for... [ a(c(?x)) -> b(c(?x)), a(b(?x)) -> c(c(?x)), a(a(?x)) -> c(c(?x)), a(b(?x)) -> c(a(?x)), b(b(?x)) -> a(a(?x)), c(b(?x)) -> c(a(?x)), c(c(?x)) -> a(b(?x)), c(b(?x)) -> c(c(?x)), b(c(?x)) -> a(c(?x)) ] Layer Preserving Decomposition failed: Can't judge Try Commutative Decomposition for... [ a(c(?x)) -> b(c(?x)), a(b(?x)) -> c(c(?x)), a(a(?x)) -> c(c(?x)), a(b(?x)) -> c(a(?x)), b(b(?x)) -> a(a(?x)), c(b(?x)) -> c(a(?x)), c(c(?x)) -> a(b(?x)), c(b(?x)) -> c(c(?x)), b(c(?x)) -> a(c(?x)) ] Outside Critical Pair: by Rules <3, 1> develop reducts from lhs term... <{}, c(a(?x_3))> develop reducts from rhs term... <{6}, a(b(?x_3))> <{}, c(c(?x_3))> Outside Critical Pair: by Rules <7, 5> develop reducts from lhs term... <{6}, a(b(?x_7))> <{}, c(c(?x_7))> develop reducts from rhs term... <{}, c(a(?x_7))> Inside Critical Pair: by Rules <5, 0> develop reducts from lhs term... <{0}, b(c(a(?x_5)))> <{}, a(c(a(?x_5)))> develop reducts from rhs term... <{8}, a(c(b(?x_5)))> <{7}, b(c(c(?x_5)))> <{5}, b(c(a(?x_5)))> <{}, b(c(b(?x_5)))> Inside Critical Pair: by Rules <6, 0> develop reducts from lhs term... <{2}, c(c(b(?x_6)))> <{3}, a(c(a(?x_6)))> <{1}, a(c(c(?x_6)))> <{}, a(a(b(?x_6)))> develop reducts from rhs term... <{8}, a(c(c(?x_6)))> <{6}, b(a(b(?x_6)))> <{}, b(c(c(?x_6)))> Inside Critical Pair: by Rules <7, 0> develop reducts from lhs term... <{0}, b(c(c(?x_7)))> <{6}, a(a(b(?x_7)))> <{}, a(c(c(?x_7)))> develop reducts from rhs term... <{8}, a(c(b(?x_7)))> <{7}, b(c(c(?x_7)))> <{5}, b(c(a(?x_7)))> <{}, b(c(b(?x_7)))> Inside Critical Pair: by Rules <4, 1> develop reducts from lhs term... <{2}, c(c(a(?x_4)))> <{2}, a(c(c(?x_4)))> <{}, a(a(a(?x_4)))> develop reducts from rhs term... <{6}, a(b(b(?x_4)))> <{7}, c(c(c(?x_4)))> <{5}, c(c(a(?x_4)))> <{}, c(c(b(?x_4)))> Inside Critical Pair: by Rules <8, 1> develop reducts from lhs term... <{2}, c(c(c(?x_8)))> <{0}, a(b(c(?x_8)))> <{}, a(a(c(?x_8)))> develop reducts from rhs term... <{6}, a(b(c(?x_8)))> <{6}, c(a(b(?x_8)))> <{}, c(c(c(?x_8)))> Inside Critical Pair: by Rules <0, 2> develop reducts from lhs term... <{3}, c(a(c(?x)))> <{1}, c(c(c(?x)))> <{8}, a(a(c(?x)))> <{}, a(b(c(?x)))> develop reducts from rhs term... <{6}, a(b(c(?x)))> <{6}, c(a(b(?x)))> <{}, c(c(c(?x)))> Inside Critical Pair: by Rules <1, 2> develop reducts from lhs term... <{0}, b(c(c(?x_1)))> <{6}, a(a(b(?x_1)))> <{}, a(c(c(?x_1)))> develop reducts from rhs term... <{6}, a(b(b(?x_1)))> <{7}, c(c(c(?x_1)))> <{5}, c(c(a(?x_1)))> <{}, c(c(b(?x_1)))> Inside Critical Pair: by Rules <3, 2> develop reducts from lhs term... <{0}, b(c(a(?x_3)))> <{}, a(c(a(?x_3)))> develop reducts from rhs term... <{6}, a(b(b(?x_3)))> <{7}, c(c(c(?x_3)))> <{5}, c(c(a(?x_3)))> <{}, c(c(b(?x_3)))> Inside Critical Pair: by Rules <4, 3> develop reducts from lhs term... <{2}, c(c(a(?x_4)))> <{2}, a(c(c(?x_4)))> <{}, a(a(a(?x_4)))> develop reducts from rhs term... <{3}, c(c(a(?x_4)))> <{1}, c(c(c(?x_4)))> <{}, c(a(b(?x_4)))> Inside Critical Pair: by Rules <8, 3> develop reducts from lhs term... <{2}, c(c(c(?x_8)))> <{0}, a(b(c(?x_8)))> <{}, a(a(c(?x_8)))> develop reducts from rhs term... <{0}, c(b(c(?x_8)))> <{}, c(a(c(?x_8)))> Inside Critical Pair: by Rules <8, 4> develop reducts from lhs term... <{0}, b(b(c(?x_8)))> <{}, b(a(c(?x_8)))> develop reducts from rhs term... <{2}, c(c(c(?x_8)))> <{0}, a(b(c(?x_8)))> <{}, a(a(c(?x_8)))> Inside Critical Pair: by Rules <4, 5> develop reducts from lhs term... <{2}, c(c(c(?x_4)))> <{}, c(a(a(?x_4)))> develop reducts from rhs term... <{3}, c(c(a(?x_4)))> <{1}, c(c(c(?x_4)))> <{}, c(a(b(?x_4)))> Inside Critical Pair: by Rules <8, 5> develop reducts from lhs term... <{0}, c(b(c(?x_8)))> <{}, c(a(c(?x_8)))> develop reducts from rhs term... <{0}, c(b(c(?x_8)))> <{}, c(a(c(?x_8)))> Inside Critical Pair: by Rules <5, 6> develop reducts from lhs term... <{6}, a(b(a(?x_5)))> <{}, c(c(a(?x_5)))> develop reducts from rhs term... <{3}, c(a(b(?x_5)))> <{1}, c(c(b(?x_5)))> <{4}, a(a(a(?x_5)))> <{}, a(b(b(?x_5)))> Inside Critical Pair: by Rules <7, 6> develop reducts from lhs term... <{6}, a(b(c(?x_7)))> <{6}, c(a(b(?x_7)))> <{}, c(c(c(?x_7)))> develop reducts from rhs term... <{3}, c(a(b(?x_7)))> <{1}, c(c(b(?x_7)))> <{4}, a(a(a(?x_7)))> <{}, a(b(b(?x_7)))> Inside Critical Pair: by Rules <4, 7> develop reducts from lhs term... <{2}, c(c(c(?x_4)))> <{}, c(a(a(?x_4)))> develop reducts from rhs term... <{6}, a(b(b(?x_4)))> <{7}, c(c(c(?x_4)))> <{5}, c(c(a(?x_4)))> <{}, c(c(b(?x_4)))> Inside Critical Pair: by Rules <8, 7> develop reducts from lhs term... <{0}, c(b(c(?x_8)))> <{}, c(a(c(?x_8)))> develop reducts from rhs term... <{6}, a(b(c(?x_8)))> <{6}, c(a(b(?x_8)))> <{}, c(c(c(?x_8)))> Inside Critical Pair: by Rules <5, 8> develop reducts from lhs term... <{8}, a(c(a(?x_5)))> <{}, b(c(a(?x_5)))> develop reducts from rhs term... <{0}, b(c(b(?x_5)))> <{7}, a(c(c(?x_5)))> <{5}, a(c(a(?x_5)))> <{}, a(c(b(?x_5)))> Inside Critical Pair: by Rules <6, 8> develop reducts from lhs term... <{3}, b(c(a(?x_6)))> <{1}, b(c(c(?x_6)))> <{}, b(a(b(?x_6)))> develop reducts from rhs term... <{0}, b(c(c(?x_6)))> <{6}, a(a(b(?x_6)))> <{}, a(c(c(?x_6)))> Inside Critical Pair: by Rules <7, 8> develop reducts from lhs term... <{8}, a(c(c(?x_7)))> <{6}, b(a(b(?x_7)))> <{}, b(c(c(?x_7)))> develop reducts from rhs term... <{0}, b(c(b(?x_7)))> <{7}, a(c(c(?x_7)))> <{5}, a(c(a(?x_7)))> <{}, a(c(b(?x_7)))> Commutative Decomposition failed: Can't judge No further decomposition possible Combined result: Can't judge 1028.trs: Failure(unknown CR) MAYBE (7954 msec.)