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

Termination of R to be shown.



   R
Dependency Pair Analysis



R contains the following Dependency Pairs:

APP(f, app(g, x)) -> APP(g, app(f, app(f, x)))
APP(f, app(g, x)) -> APP(f, app(f, x))
APP(f, app(g, x)) -> APP(f, x)
APP(f, app(h, x)) -> APP(h, app(g, x))
APP(f, app(h, x)) -> APP(g, x)

Furthermore, R contains one SCC.


   R
DPs
       →DP Problem 1
Narrowing Transformation


Dependency Pairs:

APP(f, app(g, x)) -> APP(f, x)
APP(f, app(g, x)) -> APP(f, app(f, x))


Rules:


app(f, app(g, x)) -> app(g, app(f, app(f, x)))
app(f, app(h, x)) -> app(h, app(g, x))





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

APP(f, app(g, x)) -> APP(f, app(f, x))
two new Dependency Pairs are created:

APP(f, app(g, app(g, x''))) -> APP(f, app(g, app(f, app(f, x''))))
APP(f, app(g, app(h, x''))) -> APP(f, app(h, app(g, x'')))

The transformation is resulting in one new DP problem:



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


Dependency Pairs:

APP(f, app(g, app(h, x''))) -> APP(f, app(h, app(g, x'')))
APP(f, app(g, app(g, x''))) -> APP(f, app(g, app(f, app(f, x''))))
APP(f, app(g, x)) -> APP(f, x)


Rules:


app(f, app(g, x)) -> app(g, app(f, app(f, x)))
app(f, app(h, x)) -> app(h, app(g, x))





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

APP(f, app(g, app(h, x''))) -> APP(f, app(h, app(g, x'')))
no new Dependency Pairs are created.
The transformation is resulting in one new DP problem:



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




The following remains to be proven:
Dependency Pairs:

APP(f, app(g, x)) -> APP(f, x)
APP(f, app(g, app(g, x''))) -> APP(f, app(g, app(f, app(f, x''))))


Rules:


app(f, app(g, x)) -> app(g, app(f, app(f, x)))
app(f, app(h, x)) -> app(h, app(g, x))




Termination of R could not be shown.
Duration:
0:00 minutes