Term Rewriting System R:
[x, y, z]
times(x, plus(y, s(z))) -> plus(times(x, plus(y, times(s(z), 0))), times(x, s(z)))
times(x, 0) -> 0
times(x, s(y)) -> plus(times(x, y), x)
plus(x, 0) -> x
plus(x, s(y)) -> s(plus(x, y))
Termination of R to be shown.
R
↳Dependency Pair Analysis
R contains the following Dependency Pairs:
TIMES(x, plus(y, s(z))) -> PLUS(times(x, plus(y, times(s(z), 0))), times(x, s(z)))
TIMES(x, plus(y, s(z))) -> TIMES(x, plus(y, times(s(z), 0)))
TIMES(x, plus(y, s(z))) -> PLUS(y, times(s(z), 0))
TIMES(x, plus(y, s(z))) -> TIMES(s(z), 0)
TIMES(x, plus(y, s(z))) -> TIMES(x, s(z))
TIMES(x, s(y)) -> PLUS(times(x, y), x)
TIMES(x, s(y)) -> TIMES(x, y)
PLUS(x, s(y)) -> PLUS(x, y)
Furthermore, R contains two SCCs.
R
↳DPs
→DP Problem 1
↳Size-Change Principle
→DP Problem 2
↳MRR
Dependency Pair:
PLUS(x, s(y)) -> PLUS(x, y)
Rules:
times(x, plus(y, s(z))) -> plus(times(x, plus(y, times(s(z), 0))), times(x, s(z)))
times(x, 0) -> 0
times(x, s(y)) -> plus(times(x, y), x)
plus(x, 0) -> x
plus(x, s(y)) -> s(plus(x, y))
We number the DPs as follows:
- PLUS(x, s(y)) -> PLUS(x, y)
and get the following Size-Change Graph(s):
which lead(s) to this/these maximal multigraph(s):
DP: empty set
Oriented Rules: none
We used the order Homeomorphic Embedding Order with Non-Strict Precedence.
trivial
with Argument Filtering System:
s(x1) -> s(x1)
We obtain no new DP problems.
R
↳DPs
→DP Problem 1
↳SCP
→DP Problem 2
↳Modular Removal of Rules
Dependency Pairs:
TIMES(x, s(y)) -> TIMES(x, y)
TIMES(x, plus(y, s(z))) -> TIMES(x, s(z))
TIMES(x, plus(y, s(z))) -> TIMES(x, plus(y, times(s(z), 0)))
Rules:
times(x, plus(y, s(z))) -> plus(times(x, plus(y, times(s(z), 0))), times(x, s(z)))
times(x, 0) -> 0
times(x, s(y)) -> plus(times(x, y), x)
plus(x, 0) -> x
plus(x, s(y)) -> s(plus(x, y))
We have the following set of usable rules:
plus(x, 0) -> x
plus(x, s(y)) -> s(plus(x, y))
times(x, 0) -> 0
To remove rules and DPs from this DP problem we used the following monotonic and CE-compatible order: Polynomial ordering.
Polynomial interpretation:
POL(TIMES(x1, x2)) | = 1 + x1 + x2 |
POL(plus(x1, x2)) | = x1 + x2 |
POL(0) | = 0 |
POL(times(x1, x2)) | = x1 + x2 |
POL(s(x1)) | = x1 |
We have the following set D of usable symbols: {TIMES, plus, 0, times, s}
No Dependency Pairs can be deleted.
2 non usable rules have been deleted.
The result of this processor delivers one new DP problem.
R
↳DPs
→DP Problem 1
↳SCP
→DP Problem 2
↳MRR
→DP Problem 3
↳Modular Removal of Rules
Dependency Pairs:
TIMES(x, s(y)) -> TIMES(x, y)
TIMES(x, plus(y, s(z))) -> TIMES(x, s(z))
TIMES(x, plus(y, s(z))) -> TIMES(x, plus(y, times(s(z), 0)))
Rules:
plus(x, 0) -> x
plus(x, s(y)) -> s(plus(x, y))
times(x, 0) -> 0
We have the following set of usable rules:
plus(x, 0) -> x
plus(x, s(y)) -> s(plus(x, y))
times(x, 0) -> 0
To remove rules and DPs from this DP problem we used the following monotonic and CE-compatible order: Polynomial ordering.
Polynomial interpretation:
POL(TIMES(x1, x2)) | = 1 + x1 + x2 |
POL(plus(x1, x2)) | = 1 + x1 + x2 |
POL(0) | = 0 |
POL(times(x1, x2)) | = x1 + x2 |
POL(s(x1)) | = x1 |
We have the following set D of usable symbols: {TIMES, plus, 0, times, s}
The following Dependency Pairs can be deleted as the lhs is strictly greater than the corresponding rhs:
TIMES(x, plus(y, s(z))) -> TIMES(x, s(z))
The following rules can be deleted as the lhs is strictly greater than the corresponding rhs:
plus(x, 0) -> x
The result of this processor delivers one new DP problem.
R
↳DPs
→DP Problem 1
↳SCP
→DP Problem 2
↳MRR
→DP Problem 3
↳MRR
...
→DP Problem 4
↳Modular Removal of Rules
Dependency Pairs:
TIMES(x, s(y)) -> TIMES(x, y)
TIMES(x, plus(y, s(z))) -> TIMES(x, plus(y, times(s(z), 0)))
Rules:
plus(x, s(y)) -> s(plus(x, y))
times(x, 0) -> 0
We have the following set of usable rules:
plus(x, s(y)) -> s(plus(x, y))
times(x, 0) -> 0
To remove rules and DPs from this DP problem we used the following monotonic and CE-compatible order: Polynomial ordering.
Polynomial interpretation:
POL(TIMES(x1, x2)) | = 1 + x1 + x2 |
POL(plus(x1, x2)) | = x1 + x2 |
POL(0) | = 0 |
POL(times(x1, x2)) | = x1 + x2 |
POL(s(x1)) | = 1 + x1 |
We have the following set D of usable symbols: {TIMES, plus, 0, times, s}
The following Dependency Pairs can be deleted as the lhs is strictly greater than the corresponding rhs:
TIMES(x, s(y)) -> TIMES(x, y)
No Rules can be deleted.
The result of this processor delivers one new DP problem.
R
↳DPs
→DP Problem 1
↳SCP
→DP Problem 2
↳MRR
→DP Problem 3
↳MRR
...
→DP Problem 5
↳Narrowing Transformation
Dependency Pair:
TIMES(x, plus(y, s(z))) -> TIMES(x, plus(y, times(s(z), 0)))
Rules:
plus(x, s(y)) -> s(plus(x, y))
times(x, 0) -> 0
On this DP problem, a Narrowing SCC transformation can be performed.
As a result of transforming the rule
TIMES(x, plus(y, s(z))) -> TIMES(x, plus(y, times(s(z), 0)))
one new Dependency Pair
is created:
TIMES(x, plus(y, s(z'))) -> TIMES(x, plus(y, 0))
The transformation is resulting in no new DP problems.
Termination of R successfully shown.
Duration:
0:00 minutes