Certification Problem
Input (TPDB TRS_Innermost/Transformed_CSR_innermost_04/PALINDROME_nosorts_noand_iGM)
The rewrite relation of the following TRS is considered.
active(__(__(X,Y),Z)) |
→ |
mark(__(X,__(Y,Z))) |
(1) |
active(__(X,nil)) |
→ |
mark(X) |
(2) |
active(__(nil,X)) |
→ |
mark(X) |
(3) |
active(U11(tt)) |
→ |
mark(U12(tt)) |
(4) |
active(U12(tt)) |
→ |
mark(tt) |
(5) |
active(isNePal(__(I,__(P,I)))) |
→ |
mark(U11(tt)) |
(6) |
mark(__(X1,X2)) |
→ |
active(__(mark(X1),mark(X2))) |
(7) |
mark(nil) |
→ |
active(nil) |
(8) |
mark(U11(X)) |
→ |
active(U11(mark(X))) |
(9) |
mark(tt) |
→ |
active(tt) |
(10) |
mark(U12(X)) |
→ |
active(U12(mark(X))) |
(11) |
mark(isNePal(X)) |
→ |
active(isNePal(mark(X))) |
(12) |
__(mark(X1),X2) |
→ |
__(X1,X2) |
(13) |
__(X1,mark(X2)) |
→ |
__(X1,X2) |
(14) |
__(active(X1),X2) |
→ |
__(X1,X2) |
(15) |
__(X1,active(X2)) |
→ |
__(X1,X2) |
(16) |
U11(mark(X)) |
→ |
U11(X) |
(17) |
U11(active(X)) |
→ |
U11(X) |
(18) |
U12(mark(X)) |
→ |
U12(X) |
(19) |
U12(active(X)) |
→ |
U12(X) |
(20) |
isNePal(mark(X)) |
→ |
isNePal(X) |
(21) |
isNePal(active(X)) |
→ |
isNePal(X) |
(22) |
The evaluation strategy is innermost.Property / Task
Prove or disprove termination.Answer / Result
Yes.Proof (by AProVE @ termCOMP 2023)
1 Rule Removal
Using the
linear polynomial interpretation over the naturals
[active(x1)] |
= |
1 · x1
|
[__(x1, x2)] |
= |
2 + 1 · x1 + 1 · x2
|
[mark(x1)] |
= |
1 · x1
|
[nil] |
= |
0 |
[U11(x1)] |
= |
2 + 1 · x1
|
[tt] |
= |
1 |
[U12(x1)] |
= |
2 · x1
|
[isNePal(x1)] |
= |
1 · x1
|
all of the following rules can be deleted.
active(__(X,nil)) |
→ |
mark(X) |
(2) |
active(__(nil,X)) |
→ |
mark(X) |
(3) |
active(U11(tt)) |
→ |
mark(U12(tt)) |
(4) |
active(U12(tt)) |
→ |
mark(tt) |
(5) |
active(isNePal(__(I,__(P,I)))) |
→ |
mark(U11(tt)) |
(6) |
1.1 Rule Removal
Using the
linear polynomial interpretation over the naturals
[active(x1)] |
= |
1 · x1
|
[__(x1, x2)] |
= |
2 + 2 · x1 + 1 · x2
|
[mark(x1)] |
= |
1 · x1
|
[nil] |
= |
0 |
[U11(x1)] |
= |
2 · x1
|
[tt] |
= |
0 |
[U12(x1)] |
= |
1 · x1
|
[isNePal(x1)] |
= |
1 · x1
|
all of the following rules can be deleted.
active(__(__(X,Y),Z)) |
→ |
mark(__(X,__(Y,Z))) |
(1) |
1.1.1 Rule Removal
Using the
linear polynomial interpretation over the naturals
[mark(x1)] |
= |
2 · x1
|
[__(x1, x2)] |
= |
1 + 2 · x1 + 1 · x2
|
[active(x1)] |
= |
1 · x1
|
[nil] |
= |
1 |
[U11(x1)] |
= |
1 + 2 · x1
|
[tt] |
= |
1 |
[U12(x1)] |
= |
1 + 2 · x1
|
[isNePal(x1)] |
= |
2 · x1
|
all of the following rules can be deleted.
mark(__(X1,X2)) |
→ |
active(__(mark(X1),mark(X2))) |
(7) |
mark(nil) |
→ |
active(nil) |
(8) |
mark(U11(X)) |
→ |
active(U11(mark(X))) |
(9) |
mark(tt) |
→ |
active(tt) |
(10) |
mark(U12(X)) |
→ |
active(U12(mark(X))) |
(11) |
1.1.1.1 Rule Removal
Using the
linear polynomial interpretation over the naturals
[mark(x1)] |
= |
2 + 2 · x1
|
[isNePal(x1)] |
= |
2 + 2 · x1
|
[active(x1)] |
= |
1 · x1
|
[__(x1, x2)] |
= |
1 · x1 + 1 · x2
|
[U11(x1)] |
= |
2 · x1
|
[U12(x1)] |
= |
2 · x1
|
all of the following rules can be deleted.
__(mark(X1),X2) |
→ |
__(X1,X2) |
(13) |
__(X1,mark(X2)) |
→ |
__(X1,X2) |
(14) |
U11(mark(X)) |
→ |
U11(X) |
(17) |
U12(mark(X)) |
→ |
U12(X) |
(19) |
isNePal(mark(X)) |
→ |
isNePal(X) |
(21) |
1.1.1.1.1 Rule Removal
Using the
linear polynomial interpretation over the naturals
[mark(x1)] |
= |
2 · x1
|
[isNePal(x1)] |
= |
2 + 2 · x1
|
[active(x1)] |
= |
1 · x1
|
[__(x1, x2)] |
= |
1 · x1 + 2 · x2
|
[U11(x1)] |
= |
2 · x1
|
[U12(x1)] |
= |
2 · x1
|
all of the following rules can be deleted.
mark(isNePal(X)) |
→ |
active(isNePal(mark(X))) |
(12) |
1.1.1.1.1.1 Rule Removal
Using the
Knuth Bendix order with w0 = 1 and the following precedence and weight functions
prec(active) |
= |
4 |
|
weight(active) |
= |
0 |
|
|
|
prec(U11) |
= |
1 |
|
weight(U11) |
= |
1 |
|
|
|
prec(U12) |
= |
2 |
|
weight(U12) |
= |
1 |
|
|
|
prec(isNePal) |
= |
3 |
|
weight(isNePal) |
= |
1 |
|
|
|
prec(__) |
= |
0 |
|
weight(__) |
= |
0 |
|
|
|
all of the following rules can be deleted.
__(active(X1),X2) |
→ |
__(X1,X2) |
(15) |
__(X1,active(X2)) |
→ |
__(X1,X2) |
(16) |
U11(active(X)) |
→ |
U11(X) |
(18) |
U12(active(X)) |
→ |
U12(X) |
(20) |
isNePal(active(X)) |
→ |
isNePal(X) |
(22) |
1.1.1.1.1.1.1 R is empty
There are no rules in the TRS. Hence, it is terminating.