(VAR a d k x )

(DATATYPES
   a = < >
   b = µX. < empty, cons(a,X) >
 )

(SIGNATURES
   f :: b x b -> b
   g :: b x b -> b
 )


(RULES
   f(a,empty) -> g(a,empty)
   f(a,cons(x,k)) -> f(cons(x,a),k)
   g(empty,d) -> d
   g(cons(x,k),d) -> g(k,cons(x,d))
)