Term Rewriting System R:
[y, x, z]
f(a, g(y)) -> g(g(y))
f(g(x), a) -> f(x, g(a))
f(g(x), g(y)) -> h(g(y), x, g(y))
h(g(x), y, z) -> f(y, h(x, y, z))
h(a, y, z) -> z

Innermost Termination of R to be shown.



   R
Dependency Pair Analysis



R contains the following Dependency Pairs:

F(g(x), a) -> F(x, g(a))
F(g(x), g(y)) -> H(g(y), x, g(y))
H(g(x), y, z) -> F(y, h(x, y, z))
H(g(x), y, z) -> H(x, y, z)

Furthermore, R contains one SCC.


   R
DPs
       →DP Problem 1
Argument Filtering and Ordering


Dependency Pairs:

H(g(x), y, z) -> H(x, y, z)
H(g(x), y, z) -> F(y, h(x, y, z))
F(g(x), g(y)) -> H(g(y), x, g(y))
F(g(x), a) -> F(x, g(a))


Rules:


f(a, g(y)) -> g(g(y))
f(g(x), a) -> f(x, g(a))
f(g(x), g(y)) -> h(g(y), x, g(y))
h(g(x), y, z) -> f(y, h(x, y, z))
h(a, y, z) -> z


Strategy:

innermost




The following dependency pair can be strictly oriented:

F(g(x), a) -> F(x, g(a))


The following usable rules for innermost can be oriented:

h(g(x), y, z) -> f(y, h(x, y, z))
h(a, y, z) -> z
f(a, g(y)) -> g(g(y))
f(g(x), a) -> f(x, g(a))
f(g(x), g(y)) -> h(g(y), x, g(y))


Used ordering: Lexicographic Path Order with Non-Strict Precedence with Quasi Precedence:
a > g

resulting in one new DP problem.
Used Argument Filtering System:
F(x1, x2) -> x2
g(x1) -> g
H(x1, x2, x3) -> x3
h(x1, x2, x3) -> x3
f(x1, x2) -> x2


   R
DPs
       →DP Problem 1
AFS
           →DP Problem 2
Narrowing Transformation


Dependency Pairs:

H(g(x), y, z) -> H(x, y, z)
H(g(x), y, z) -> F(y, h(x, y, z))
F(g(x), g(y)) -> H(g(y), x, g(y))


Rules:


f(a, g(y)) -> g(g(y))
f(g(x), a) -> f(x, g(a))
f(g(x), g(y)) -> h(g(y), x, g(y))
h(g(x), y, z) -> f(y, h(x, y, z))
h(a, y, z) -> z


Strategy:

innermost




On this DP problem, a Narrowing SCC transformation can be performed.
As a result of transforming the rule

H(g(x), y, z) -> F(y, h(x, y, z))
two new Dependency Pairs are created:

H(g(g(x'')), y'', z'') -> F(y'', f(y'', h(x'', y'', z'')))
H(g(a), y'', z'') -> F(y'', z'')

The transformation is resulting in one new DP problem:



   R
DPs
       →DP Problem 1
AFS
           →DP Problem 2
Nar
             ...
               →DP Problem 3
Remaining Obligation(s)




The following remains to be proven:
Dependency Pairs:

H(g(a), y'', z'') -> F(y'', z'')
F(g(x), g(y)) -> H(g(y), x, g(y))
H(g(g(x'')), y'', z'') -> F(y'', f(y'', h(x'', y'', z'')))
H(g(x), y, z) -> H(x, y, z)


Rules:


f(a, g(y)) -> g(g(y))
f(g(x), a) -> f(x, g(a))
f(g(x), g(y)) -> h(g(y), x, g(y))
h(g(x), y, z) -> f(y, h(x, y, z))
h(a, y, z) -> z


Strategy:

innermost



Innermost Termination of R could not be shown.
Duration:
0:03 minutes