Term Rewriting System R:
[X, Z, Y]
h(X, Z) -> f(X, s(X), Z)
f(X, Y, g(X, Y)) -> h(0, g(X, Y))
g(0, Y) -> 0
g(X, s(Y)) -> g(X, Y)
Termination of R to be shown.
R
↳Removing Redundant Rules
Removing the following rules from R which fullfill a polynomial ordering:
g(0, Y) -> 0
where the Polynomial interpretation:
POL(0) | = 0 |
POL(g(x1, x2)) | = 1 + x1 + x2 |
POL(h(x1, x2)) | = 2·x1 + x2 |
POL(s(x1)) | = x1 |
POL(f(x1, x2, x3)) | = x1 + x2 + x3 |
was used.
Not all Rules of R can be deleted, so we still have to regard a part of R.
R
↳RRRPolo
→TRS2
↳Dependency Pair Analysis
R contains the following Dependency Pairs:
F(X, Y, g(X, Y)) -> H(0, g(X, Y))
G(X, s(Y)) -> G(X, Y)
H(X, Z) -> F(X, s(X), Z)
Furthermore, R contains two SCCs.
R
↳RRRPolo
→TRS2
↳DPs
→DP Problem 1
↳Size-Change Principle
→DP Problem 2
↳NonTerm
Dependency Pair:
G(X, s(Y)) -> G(X, Y)
Rules:
f(X, Y, g(X, Y)) -> h(0, g(X, Y))
g(X, s(Y)) -> g(X, Y)
h(X, Z) -> f(X, s(X), Z)
We number the DPs as follows:
- G(X, s(Y)) -> G(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
↳RRRPolo
→TRS2
↳DPs
→DP Problem 1
↳SCP
→DP Problem 2
↳Non Termination
Dependency Pairs:
H(X, Z) -> F(X, s(X), Z)
F(X, Y, g(X, Y)) -> H(0, g(X, Y))
Rules:
f(X, Y, g(X, Y)) -> h(0, g(X, Y))
g(X, s(Y)) -> g(X, Y)
h(X, Z) -> f(X, s(X), Z)
Found an infinite P-chain over R:
P =
H(X, Z) -> F(X, s(X), Z)
F(X, Y, g(X, Y)) -> H(0, g(X, Y))
R =
f(X, Y, g(X, Y)) -> h(0, g(X, Y))
g(X, s(Y)) -> g(X, Y)
h(X, Z) -> f(X, s(X), Z)
s = F(0, s(0), g(0, s(0)))
evaluates to t =F(0, s(0), g(0, s(0)))
Thus, s starts an infinite chain.
Non-Termination of R could be shown.
Duration:
0:00 minutes