Term Rewriting System R:
[x, y, z]
flatten(nil) -> nil
flatten(unit(x)) -> flatten(x)
flatten(++(x, y)) -> ++(flatten(x), flatten(y))
flatten(++(unit(x), y)) -> ++(flatten(x), flatten(y))
flatten(flatten(x)) -> flatten(x)
rev(nil) -> nil
rev(unit(x)) -> unit(x)
rev(++(x, y)) -> ++(rev(y), rev(x))
rev(rev(x)) -> x
++(x, nil) -> x
++(nil, y) -> y
++(++(x, y), z) -> ++(x, ++(y, z))

Termination of R to be shown.



   R
Removing Redundant Rules



Removing the following rules from R which fullfill a polynomial ordering:

flatten(nil) -> nil
++(x, nil) -> x
++(nil, y) -> y

where the Polynomial interpretation:
  POL(unit(x1))=  x1  
  POL(rev(x1))=  x1  
  POL(flatten(x1))=  2·x1  
  POL(++(x1, x2))=  x1 + x2  
  POL(nil)=  1  
was used.

Not all Rules of R can be deleted, so we still have to regard a part of R.


   R
RRRPolo
       →TRS2
Removing Redundant Rules



Removing the following rules from R which fullfill a polynomial ordering:

rev(nil) -> nil

where the Polynomial interpretation:
  POL(rev(x1))=  2·x1  
  POL(unit(x1))=  x1  
  POL(flatten(x1))=  x1  
  POL(++(x1, x2))=  x1 + x2  
  POL(nil)=  1  
was used.

Not all Rules of R can be deleted, so we still have to regard a part of R.


   R
RRRPolo
       →TRS2
RRRPolo
           →TRS3
Removing Redundant Rules



Removing the following rules from R which fullfill a polynomial ordering:

rev(++(x, y)) -> ++(rev(y), rev(x))

where the Polynomial interpretation:
  POL(rev(x1))=  2·x1  
  POL(unit(x1))=  x1  
  POL(flatten(x1))=  x1  
  POL(++(x1, x2))=  1 + x1 + x2  
was used.

Not all Rules of R can be deleted, so we still have to regard a part of R.


   R
RRRPolo
       →TRS2
RRRPolo
           →TRS3
RRRPolo
             ...
               →TRS4
Removing Redundant Rules



Removing the following rules from R which fullfill a polynomial ordering:

flatten(unit(x)) -> flatten(x)
flatten(++(unit(x), y)) -> ++(flatten(x), flatten(y))

where the Polynomial interpretation:
  POL(unit(x1))=  1 + x1  
  POL(rev(x1))=  x1  
  POL(flatten(x1))=  x1  
  POL(++(x1, x2))=  x1 + x2  
was used.

Not all Rules of R can be deleted, so we still have to regard a part of R.


   R
RRRPolo
       →TRS2
RRRPolo
           →TRS3
RRRPolo
             ...
               →TRS5
Removing Redundant Rules



Removing the following rules from R which fullfill a polynomial ordering:

flatten(flatten(x)) -> flatten(x)

where the Polynomial interpretation:
  POL(rev(x1))=  x1  
  POL(unit(x1))=  x1  
  POL(flatten(x1))=  1 + 2·x1  
  POL(++(x1, x2))=  1 + x1 + x2  
was used.

Not all Rules of R can be deleted, so we still have to regard a part of R.


   R
RRRPolo
       →TRS2
RRRPolo
           →TRS3
RRRPolo
             ...
               →TRS6
Removing Redundant Rules



Removing the following rules from R which fullfill a polynomial ordering:

rev(rev(x)) -> x
rev(unit(x)) -> unit(x)

where the Polynomial interpretation:
  POL(rev(x1))=  1 + x1  
  POL(unit(x1))=  x1  
  POL(flatten(x1))=  x1  
  POL(++(x1, x2))=  x1 + x2  
was used.

Not all Rules of R can be deleted, so we still have to regard a part of R.


   R
RRRPolo
       →TRS2
RRRPolo
           →TRS3
RRRPolo
             ...
               →TRS7
Removing Redundant Rules



Removing the following rules from R which fullfill a polynomial ordering:

flatten(++(x, y)) -> ++(flatten(x), flatten(y))

where the Polynomial interpretation:
  POL(flatten(x1))=  2·x1  
  POL(++(x1, x2))=  1 + x1 + x2  
was used.

Not all Rules of R can be deleted, so we still have to regard a part of R.


   R
RRRPolo
       →TRS2
RRRPolo
           →TRS3
RRRPolo
             ...
               →TRS8
Removing Redundant Rules



Removing the following rules from R which fullfill a polynomial ordering:

++(++(x, y), z) -> ++(x, ++(y, z))

where the Polynomial interpretation:
  POL(++(x1, x2))=  1 + 2·x1 + x2  
was used.

All Rules of R can be deleted.


   R
RRRPolo
       →TRS2
RRRPolo
           →TRS3
RRRPolo
             ...
               →TRS9
Overlay and local confluence Check



The TRS is overlay and locally confluent (all critical pairs are trivially joinable).Hence, we can switch to innermost.


   R
RRRPolo
       →TRS2
RRRPolo
           →TRS3
RRRPolo
             ...
               →TRS10
Dependency Pair Analysis



R contains no Dependency Pairs and therefore no SCCs.

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