Term Rewriting System R:
[x, y]
f(x, c(y)) -> f(x, s(f(y, y)))
f(s(x), s(y)) -> f(x, s(c(s(y))))

Innermost Termination of R to be shown.



   R
Dependency Pair Analysis



R contains the following Dependency Pairs:

F(x, c(y)) -> F(x, s(f(y, y)))
F(x, c(y)) -> F(y, y)
F(s(x), s(y)) -> F(x, s(c(s(y))))

Furthermore, R contains two SCCs.


   R
DPs
       →DP Problem 1
Instantiation Transformation
       →DP Problem 2
Inst


Dependency Pair:

F(s(x), s(y)) -> F(x, s(c(s(y))))


Rules:


f(x, c(y)) -> f(x, s(f(y, y)))
f(s(x), s(y)) -> f(x, s(c(s(y))))


Strategy:

innermost




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

F(s(x), s(y)) -> F(x, s(c(s(y))))
one new Dependency Pair is created:

F(s(x''), s(c(s(y'')))) -> F(x'', s(c(s(c(s(y''))))))

The transformation is resulting in one new DP problem:



   R
DPs
       →DP Problem 1
Inst
           →DP Problem 3
Instantiation Transformation
       →DP Problem 2
Inst


Dependency Pair:

F(s(x''), s(c(s(y'')))) -> F(x'', s(c(s(c(s(y''))))))


Rules:


f(x, c(y)) -> f(x, s(f(y, y)))
f(s(x), s(y)) -> f(x, s(c(s(y))))


Strategy:

innermost




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

F(s(x''), s(c(s(y'')))) -> F(x'', s(c(s(c(s(y''))))))
one new Dependency Pair is created:

F(s(x''''), s(c(s(c(s(y'''')))))) -> F(x'''', s(c(s(c(s(c(s(y''''))))))))

The transformation is resulting in one new DP problem:



   R
DPs
       →DP Problem 1
Inst
           →DP Problem 3
Inst
             ...
               →DP Problem 4
Argument Filtering and Ordering
       →DP Problem 2
Inst


Dependency Pair:

F(s(x''''), s(c(s(c(s(y'''')))))) -> F(x'''', s(c(s(c(s(c(s(y''''))))))))


Rules:


f(x, c(y)) -> f(x, s(f(y, y)))
f(s(x), s(y)) -> f(x, s(c(s(y))))


Strategy:

innermost




The following dependency pair can be strictly oriented:

F(s(x''''), s(c(s(c(s(y'''')))))) -> F(x'''', s(c(s(c(s(c(s(y''''))))))))


There are no usable rules for innermost that need to be oriented.
Used ordering: Lexicographic Path Order with Non-Strict Precedence with Quasi Precedence:
F > c
F > s

resulting in one new DP problem.
Used Argument Filtering System:
F(x1, x2) -> F(x1, x2)
s(x1) -> s(x1)
c(x1) -> c(x1)


   R
DPs
       →DP Problem 1
Inst
           →DP Problem 3
Inst
             ...
               →DP Problem 5
Dependency Graph
       →DP Problem 2
Inst


Dependency Pair:


Rules:


f(x, c(y)) -> f(x, s(f(y, y)))
f(s(x), s(y)) -> f(x, s(c(s(y))))


Strategy:

innermost




Using the Dependency Graph resulted in no new DP problems.


   R
DPs
       →DP Problem 1
Inst
       →DP Problem 2
Instantiation Transformation


Dependency Pair:

F(x, c(y)) -> F(y, y)


Rules:


f(x, c(y)) -> f(x, s(f(y, y)))
f(s(x), s(y)) -> f(x, s(c(s(y))))


Strategy:

innermost




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

F(x, c(y)) -> F(y, y)
one new Dependency Pair is created:

F(c(y''), c(y'')) -> F(y'', y'')

The transformation is resulting in one new DP problem:



   R
DPs
       →DP Problem 1
Inst
       →DP Problem 2
Inst
           →DP Problem 6
Forward Instantiation Transformation


Dependency Pair:

F(c(y''), c(y'')) -> F(y'', y'')


Rules:


f(x, c(y)) -> f(x, s(f(y, y)))
f(s(x), s(y)) -> f(x, s(c(s(y))))


Strategy:

innermost




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

F(c(y''), c(y'')) -> F(y'', y'')
one new Dependency Pair is created:

F(c(c(y''''')), c(c(y'''''))) -> F(c(y'''''), c(y'''''))

The transformation is resulting in one new DP problem:



   R
DPs
       →DP Problem 1
Inst
       →DP Problem 2
Inst
           →DP Problem 6
FwdInst
             ...
               →DP Problem 7
Argument Filtering and Ordering


Dependency Pair:

F(c(c(y''''')), c(c(y'''''))) -> F(c(y'''''), c(y'''''))


Rules:


f(x, c(y)) -> f(x, s(f(y, y)))
f(s(x), s(y)) -> f(x, s(c(s(y))))


Strategy:

innermost




The following dependency pair can be strictly oriented:

F(c(c(y''''')), c(c(y'''''))) -> F(c(y'''''), c(y'''''))


There are no usable rules for innermost that need to be oriented.
Used ordering: Lexicographic Path Order with Non-Strict Precedence with Quasi Precedence:
trivial

resulting in one new DP problem.
Used Argument Filtering System:
F(x1, x2) -> F(x1, x2)
c(x1) -> c(x1)


   R
DPs
       →DP Problem 1
Inst
       →DP Problem 2
Inst
           →DP Problem 6
FwdInst
             ...
               →DP Problem 8
Dependency Graph


Dependency Pair:


Rules:


f(x, c(y)) -> f(x, s(f(y, y)))
f(s(x), s(y)) -> f(x, s(c(s(y))))


Strategy:

innermost




Using the Dependency Graph resulted in no new DP problems.

Innermost Termination of R successfully shown.
Duration:
0:00 minutes