(VAR x1 x2 x3 x4 x5 x7 x9 )
(STRATEGY INNERMOST)
(RULES 
        walk#1(Leaf(x2)) -> cons_x(x2)
        walk#1(Node(x5,x3)) -> comp_f_g(walk#1(x5),walk#1(x3))
        comp_f_g#1(comp_f_g(x4,x5),comp_f_g(x2,x3),x1) -> comp_f_g#1(x4,x5,comp_f_g#1(x2,x3,x1))
        comp_f_g#1(comp_f_g(x7,x9),cons_x(x2),x4) -> comp_f_g#1(x7,x9,Cons(x2,x4))
        comp_f_g#1(cons_x(x2),comp_f_g(x5,x7),x3) -> Cons(x2,comp_f_g#1(x5,x7,x3))
        comp_f_g#1(cons_x(x5),cons_x(x2),x4) -> Cons(x5,Cons(x2,x4))
        main(Leaf(x4)) -> Cons(x4,Nil)
        main(Node(x9,x5)) -> comp_f_g#1(walk#1(x9),walk#1(x5),Nil)
        
)