Certification Problem
Input (TPDB TRS_Standard/SK90/2.10)
The rewrite relation of the following TRS is considered.
minus(0) |
→ |
0 |
(1) |
+(x,0) |
→ |
x |
(2) |
+(0,y) |
→ |
y |
(3) |
+(minus(1),1) |
→ |
0 |
(4) |
minus(minus(x)) |
→ |
x |
(5) |
+(x,minus(y)) |
→ |
minus(+(minus(x),y)) |
(6) |
+(x,+(y,z)) |
→ |
+(+(x,y),z) |
(7) |
+(minus(+(x,1)),1) |
→ |
minus(x) |
(8) |
Property / Task
Prove or disprove termination.Answer / Result
Yes.Proof (by ttt2 @ termCOMP 2023)
1 Rule Removal
Using the
linear polynomial interpretation over (3 x 3)-matrices with strict dimension 1
over the naturals
[minus(x1)] |
= |
· x1 +
|
[1] |
= |
|
[0] |
= |
|
[+(x1, x2)] |
= |
· x1 + · x2 +
|
all of the following rules can be deleted.
+(minus(1),1) |
→ |
0 |
(4) |
+(minus(+(x,1)),1) |
→ |
minus(x) |
(8) |
1.1 Rule Removal
Using the
linear polynomial interpretation over (4 x 4)-matrices with strict dimension 1
over the naturals
[minus(x1)] |
= |
|
1 |
0 |
0 |
0 |
0 |
0 |
0 |
1 |
0 |
0 |
1 |
0 |
0 |
1 |
0 |
0 |
|
|
· x1 +
|
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
|
|
|
[0] |
= |
|
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
1 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
|
|
|
[+(x1, x2)] |
= |
|
1 |
0 |
0 |
0 |
0 |
1 |
0 |
0 |
0 |
0 |
1 |
0 |
0 |
0 |
0 |
1 |
|
|
· x1 +
|
1 |
0 |
1 |
0 |
0 |
1 |
0 |
0 |
0 |
1 |
1 |
1 |
0 |
0 |
0 |
1 |
|
|
· x2 +
|
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
|
|
|
all of the following rules can be deleted.
1.1.1 Rule Removal
Using the
linear polynomial interpretation over (3 x 3)-matrices with strict dimension 1
over the naturals
[minus(x1)] |
= |
· x1 +
|
[0] |
= |
|
[+(x1, x2)] |
= |
· x1 + · x2 +
|
all of the following rules can be deleted.
1.1.1.1 Rule Removal
Using the
linear polynomial interpretation over (3 x 3)-matrices with strict dimension 1
over the naturals
[minus(x1)] |
= |
· x1 +
|
[0] |
= |
|
[+(x1, x2)] |
= |
· x1 + · x2 +
|
all of the following rules can be deleted.
+(x,+(y,z)) |
→ |
+(+(x,y),z) |
(7) |
1.1.1.1.1 Rule Removal
Using the
linear polynomial interpretation over (3 x 3)-matrices with strict dimension 1
over the naturals
[minus(x1)] |
= |
· x1 +
|
[0] |
= |
|
[+(x1, x2)] |
= |
· x1 + · x2 +
|
all of the following rules can be deleted.
+(x,minus(y)) |
→ |
minus(+(minus(x),y)) |
(6) |
1.1.1.1.1.1 Rule Removal
Using the
Weighted Path Order with the following precedence and status
prec(minus) |
= |
0 |
|
status(minus) |
= |
[1] |
|
list-extension(minus) |
= |
Lex |
prec(0) |
= |
0 |
|
status(0) |
= |
[] |
|
list-extension(0) |
= |
Lex |
and the following
Max-polynomial interpretation
[minus(x1)] |
=
|
max(0, 0 + 1 · x1) |
[0] |
=
|
max(0) |
all of the following rules can be deleted.
minus(0) |
→ |
0 |
(1) |
minus(minus(x)) |
→ |
x |
(5) |
1.1.1.1.1.1.1 R is empty
There are no rules in the TRS. Hence, it is terminating.