(GOAL COMPLEXITY)
(STARTTERM CONSTRUCTOR-BASED)
(STRATEGY INNERMOST)
(STRATEGY
    INNERMOST)

(VAR
    X X1 X2 Y Z)
(DATATYPES
    A = µX.< 0, nil, s(X), cons(X, X), n__fst(X, X), n__from(X), n__add(X, X), n__len(X) >)
(SIGNATURES
    fst :: [A x A] -> A
    from :: [A] -> A
    add :: [A x A] -> A
    len :: [A] -> A
    activate :: [A] -> A)
(RULES
    fst(0(),Z) -> nil()
    fst(s(X),cons(Y,Z)) -> cons(Y
                               ,n__fst(activate(X)
                                      ,activate(Z)))
    from(X) -> cons(X,n__from(s(X)))
    add(0(),X) -> X
    add(s(X),Y) ->
      s(n__add(activate(X),Y))
    len(nil()) -> 0()
    len(cons(X,Z)) ->
      s(n__len(activate(Z)))
    fst(X1,X2) -> n__fst(X1,X2)
    from(X) -> n__from(X)
    add(X1,X2) -> n__add(X1,X2)
    len(X) -> n__len(X)
    activate(n__fst(X1,X2)) ->
      fst(X1,X2)
    activate(n__from(X)) -> from(X)
    activate(n__add(X1,X2)) ->
      add(X1,X2)
    activate(n__len(X)) -> len(X)
    activate(X) -> X)