Term Rewriting System R:
[x, y]
f(g(x), s(0), y) -> f(g(s(0)), y, g(x))
g(s(x)) -> s(g(x))
g(0) -> 0
Termination of R to be shown.
R
↳Dependency Pair Analysis
R contains the following Dependency Pairs:
F(g(x), s(0), y) -> F(g(s(0)), y, g(x))
F(g(x), s(0), y) -> G(s(0))
G(s(x)) -> G(x)
Furthermore, R contains two SCCs.
R
↳DPs
→DP Problem 1
↳Size-Change Principle
→DP Problem 2
↳MRR
Dependency Pair:
G(s(x)) -> G(x)
Rules:
f(g(x), s(0), y) -> f(g(s(0)), y, g(x))
g(s(x)) -> s(g(x))
g(0) -> 0
We number the DPs as follows:
- G(s(x)) -> G(x)
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 Pair:
F(g(x), s(0), y) -> F(g(s(0)), y, g(x))
Rules:
f(g(x), s(0), y) -> f(g(s(0)), y, g(x))
g(s(x)) -> s(g(x))
g(0) -> 0
We have the following set of usable rules:
g(s(x)) -> s(g(x))
g(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(0) | = 0 |
POL(g(x1)) | = x1 |
POL(s(x1)) | = x1 |
POL(F(x1, x2, x3)) | = 1 + x1 + x2 + x3 |
We have the following set D of usable symbols: {0, g, s, F}
No Dependency Pairs can be deleted.
1 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
↳Non Termination
Dependency Pair:
F(g(x), s(0), y) -> F(g(s(0)), y, g(x))
Rules:
g(s(x)) -> s(g(x))
g(0) -> 0
Found an infinite P-chain over R:
P =
F(g(x), s(0), y) -> F(g(s(0)), y, g(x))
R =
g(s(x)) -> s(g(x))
g(0) -> 0
s = F(g(s(0)), g(s(0)), g(s(0)))
evaluates to t =F(g(s(0)), g(s(0)), g(s(0)))
Thus, s starts an infinite chain.
Non-Termination of R could be shown.
Duration:
0:02 minutes