Term Rewriting System R:
[f, x, xs, y, ys]
app(app(map, f), nil) -> nil
app(app(map, f), app(app(cons, x), xs)) -> app(app(cons, app(f, x)), app(app(map, f), xs))
app(app(le, 0), y) -> true
app(app(le, app(s, x)), 0) -> false
app(app(le, app(s, x)), app(s, y)) -> app(app(le, x), y)
app(app(maxlist, x), app(app(cons, y), ys)) -> app(app(if, app(app(le, x), y)), app(app(maxlist, y), ys))
app(app(maxlist, x), nil) -> x
app(height, app(app(node, x), xs)) -> app(s, app(app(maxlist, 0), app(app(map, height), xs)))

Innermost Termination of R to be shown. 



   R
     ↳Dependency Pair Analysis



R contains the following Dependency Pairs:

APP(app(map, f), app(app(cons, x), xs)) -> APP(app(cons, app(f, x)), app(app(map, f), xs))
APP(app(map, f), app(app(cons, x), xs)) -> APP(cons, app(f, x))
APP(app(map, f), app(app(cons, x), xs)) -> APP(f, x)
APP(app(map, f), app(app(cons, x), xs)) -> APP(app(map, f), xs)
APP(app(le, app(s, x)), app(s, y)) -> APP(app(le, x), y)
APP(app(le, app(s, x)), app(s, y)) -> APP(le, x)
APP(app(maxlist, x), app(app(cons, y), ys)) -> APP(app(if, app(app(le, x), y)), app(app(maxlist, y), ys))
APP(app(maxlist, x), app(app(cons, y), ys)) -> APP(if, app(app(le, x), y))
APP(app(maxlist, x), app(app(cons, y), ys)) -> APP(app(le, x), y)
APP(app(maxlist, x), app(app(cons, y), ys)) -> APP(le, x)
APP(app(maxlist, x), app(app(cons, y), ys)) -> APP(app(maxlist, y), ys)
APP(app(maxlist, x), app(app(cons, y), ys)) -> APP(maxlist, y)
APP(height, app(app(node, x), xs)) -> APP(s, app(app(maxlist, 0), app(app(map, height), xs)))
APP(height, app(app(node, x), xs)) -> APP(app(maxlist, 0), app(app(map, height), xs))
APP(height, app(app(node, x), xs)) -> APP(maxlist, 0)
APP(height, app(app(node, x), xs)) -> APP(app(map, height), xs)
APP(height, app(app(node, x), xs)) -> APP(map, height)

Furthermore, R contains three SCCs. 


   R
     ↳DPs
       →DP Problem 1
         ↳Usable Rules (Innermost)
       →DP Problem 2
         ↳UsableRules
       →DP Problem 3
         ↳UsableRules


Dependency Pair:

APP(app(le, app(s, x)), app(s, y)) -> APP(app(le, x), y)


Rules:


app(app(map, f), nil) -> nil
app(app(map, f), app(app(cons, x), xs)) -> app(app(cons, app(f, x)), app(app(map, f), xs))
app(app(le, 0), y) -> true
app(app(le, app(s, x)), 0) -> false
app(app(le, app(s, x)), app(s, y)) -> app(app(le, x), y)
app(app(maxlist, x), app(app(cons, y), ys)) -> app(app(if, app(app(le, x), y)), app(app(maxlist, y), ys))
app(app(maxlist, x), nil) -> x
app(height, app(app(node, x), xs)) -> app(s, app(app(maxlist, 0), app(app(map, height), xs)))


Strategy:

innermost




As we are in the innermost case, we can delete all 8 non-usable-rules.


   R
     ↳DPs
       →DP Problem 1
         ↳UsableRules
           →DP Problem 4
             ↳A-Transformation
       →DP Problem 2
         ↳UsableRules
       →DP Problem 3
         ↳UsableRules


Dependency Pair:

APP(app(le, app(s, x)), app(s, y)) -> APP(app(le, x), y)


Rule:

none


Strategy:

innermost




We have an applicative DP problem with proper arity. Thus we can use the A-Transformation to obtain one new DP problem which consists of the A-transformed TRSs.


   R
     ↳DPs
       →DP Problem 1
         ↳UsableRules
           →DP Problem 4
             ↳ATrans
             ...
               →DP Problem 5
                 ↳Size-Change Principle
       →DP Problem 2
         ↳UsableRules
       →DP Problem 3
         ↳UsableRules


Dependency Pair:

LE(s(x), s(y)) -> LE(x, y)


Rule:

none


Strategy:

innermost




We number the DPs as follows:
  1. LE(s(x), s(y)) -> LE(x, y)
and get the following Size-Change Graph(s):
{1} , {1}
1>1
2>2

which lead(s) to this/these maximal multigraph(s):
{1} , {1}
1>1
2>2

DP: empty set
Oriented Rules: none

We used the order Homeomorphic Embedding Order with Non-Strict Precedence.
trivial

with Argument Filtering System:
s(x1) -> s(x1)

We obtain no new DP problems. 


   R
     ↳DPs
       →DP Problem 1
         ↳UsableRules
       →DP Problem 2
         ↳Usable Rules (Innermost)
       →DP Problem 3
         ↳UsableRules


Dependency Pair:

APP(app(maxlist, x), app(app(cons, y), ys)) -> APP(app(maxlist, y), ys)


Rules:


app(app(map, f), nil) -> nil
app(app(map, f), app(app(cons, x), xs)) -> app(app(cons, app(f, x)), app(app(map, f), xs))
app(app(le, 0), y) -> true
app(app(le, app(s, x)), 0) -> false
app(app(le, app(s, x)), app(s, y)) -> app(app(le, x), y)
app(app(maxlist, x), app(app(cons, y), ys)) -> app(app(if, app(app(le, x), y)), app(app(maxlist, y), ys))
app(app(maxlist, x), nil) -> x
app(height, app(app(node, x), xs)) -> app(s, app(app(maxlist, 0), app(app(map, height), xs)))


Strategy:

innermost




As we are in the innermost case, we can delete all 8 non-usable-rules.


   R
     ↳DPs
       →DP Problem 1
         ↳UsableRules
       →DP Problem 2
         ↳UsableRules
           →DP Problem 6
             ↳A-Transformation
       →DP Problem 3
         ↳UsableRules


Dependency Pair:

APP(app(maxlist, x), app(app(cons, y), ys)) -> APP(app(maxlist, y), ys)


Rule:

none


Strategy:

innermost




We have an applicative DP problem with proper arity. Thus we can use the A-Transformation to obtain one new DP problem which consists of the A-transformed TRSs.


   R
     ↳DPs
       →DP Problem 1
         ↳UsableRules
       →DP Problem 2
         ↳UsableRules
           →DP Problem 6
             ↳ATrans
             ...
               →DP Problem 7
                 ↳Size-Change Principle
       →DP Problem 3
         ↳UsableRules


Dependency Pair:

MAXLIST(x, cons(y, ys)) -> MAXLIST(y, ys)


Rule:

none


Strategy:

innermost




We number the DPs as follows:
  1. MAXLIST(x, cons(y, ys)) -> MAXLIST(y, ys)
and get the following Size-Change Graph(s):
{1} , {1}
2>1
2>2

which lead(s) to this/these maximal multigraph(s):
{1} , {1}
2>1
2>2

DP: empty set
Oriented Rules: none

We used the order Homeomorphic Embedding Order with Non-Strict Precedence.
trivial

with Argument Filtering System:
cons(x1, x2) -> cons(x1, x2)

We obtain no new DP problems. 


   R
     ↳DPs
       →DP Problem 1
         ↳UsableRules
       →DP Problem 2
         ↳UsableRules
       →DP Problem 3
         ↳Usable Rules (Innermost)


Dependency Pairs:

APP(height, app(app(node, x), xs)) -> APP(app(map, height), xs)
APP(app(map, f), app(app(cons, x), xs)) -> APP(app(map, f), xs)
APP(app(map, f), app(app(cons, x), xs)) -> APP(f, x)


Rules:


app(app(map, f), nil) -> nil
app(app(map, f), app(app(cons, x), xs)) -> app(app(cons, app(f, x)), app(app(map, f), xs))
app(app(le, 0), y) -> true
app(app(le, app(s, x)), 0) -> false
app(app(le, app(s, x)), app(s, y)) -> app(app(le, x), y)
app(app(maxlist, x), app(app(cons, y), ys)) -> app(app(if, app(app(le, x), y)), app(app(maxlist, y), ys))
app(app(maxlist, x), nil) -> x
app(height, app(app(node, x), xs)) -> app(s, app(app(maxlist, 0), app(app(map, height), xs)))


Strategy:

innermost




As we are in the innermost case, we can delete all 8 non-usable-rules.


   R
     ↳DPs
       →DP Problem 1
         ↳UsableRules
       →DP Problem 2
         ↳UsableRules
       →DP Problem 3
         ↳UsableRules
           →DP Problem 8
             ↳Size-Change Principle


Dependency Pairs:

APP(height, app(app(node, x), xs)) -> APP(app(map, height), xs)
APP(app(map, f), app(app(cons, x), xs)) -> APP(app(map, f), xs)
APP(app(map, f), app(app(cons, x), xs)) -> APP(f, x)


Rule:

none


Strategy:

innermost




We number the DPs as follows:
  1. APP(height, app(app(node, x), xs)) -> APP(app(map, height), xs)
  2. APP(app(map, f), app(app(cons, x), xs)) -> APP(app(map, f), xs)
  3. APP(app(map, f), app(app(cons, x), xs)) -> APP(f, x)
and get the following Size-Change Graph(s):
{1} , {1}
2>2
{2} , {2}
1=1
2>2
{3} , {3}
1>1
2>2

which lead(s) to this/these maximal multigraph(s):
{2} , {2}
1=1
2>2
{3} , {3}
1>1
2>2
{2} , {3}
1>1
2>2
{3} , {1}
2>2
{3} , {2}
1>1
2>2
{1} , {3}
2>2
{3} , {2}
2>2
{2} , {1}
2>2
{2} , {2}
1>1
2>2
{3} , {3}
2>2
{2} , {2}
2>2
{2} , {3}
2>2

DP: empty set
Oriented Rules: none

We used the order Homeomorphic Embedding Order with Non-Strict Precedence.
trivial

with Argument Filtering System:
app(x1, x2) -> app(x1, x2)

We obtain no new DP problems.

Innermost Termination of R successfully shown.
Duration:
0:01 minutes