(0) Obligation:
Q restricted rewrite system:
The TRS R consists of the following rules:
f(0, 1, X) → h(X, X)
h(0, X) → f(0, X, X)
g(X, Y) → X
g(X, Y) → Y
Q is empty.
(1) DependencyPairsProof (EQUIVALENT transformation)
Using Dependency Pairs [AG00,LPAR04] we result in the following initial DP problem.
(2) Obligation:
Q DP problem:
The TRS P consists of the following rules:
F(0, 1, X) → H(X, X)
H(0, X) → F(0, X, X)
The TRS R consists of the following rules:
f(0, 1, X) → h(X, X)
h(0, X) → f(0, X, X)
g(X, Y) → X
g(X, Y) → Y
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
(3) NonTerminationLoopProof (EQUIVALENT transformation)
We used the non-termination processor [FROCOS05] to show that the DP problem is infinite.
Found a loop by narrowing to the left:
s =
H(
g(
X,
0),
g(
1,
Y)) evaluates to t =
H(
g(
1,
Y),
g(
1,
Y))
Thus s starts an infinite chain as s semiunifies with t with the following substitutions:
- Matcher: [ ]
- Semiunifier: [X / 1, Y / 0]
Rewriting sequenceH(g(1, 0), g(1, 0)) →
H(
0,
g(
1,
0))
with rule
g(
X,
Y') →
Y' at position [0] and matcher [
X /
1,
Y' /
0]
H(0, g(1, 0)) →
F(
0,
g(
1,
0),
g(
1,
0))
with rule
H(
0,
X') →
F(
0,
X',
X') at position [] and matcher [
X' /
g(
1,
0)]
F(0, g(1, 0), g(1, 0)) →
F(
0,
1,
g(
1,
0))
with rule
g(
X',
Y) →
X' at position [1] and matcher [
X' /
1,
Y /
0]
F(0, 1, g(1, 0)) →
H(
g(
1,
0),
g(
1,
0))
with rule
F(
0,
1,
X) →
H(
X,
X)
Now applying the matcher to the start term leads to a term which is equal to the last term in the rewriting sequence
All these steps are and every following step will be a correct step w.r.t to Q.
(4) NO