(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.)