(VAR f g l x xs )
(RULES 
        app(app(app(compose,f),g),x) -> app(g,app(f,x))
        app(reverse,l) -> app(app(reverse2,l),nil)
        app(app(reverse2,nil),l) -> l
        app(app(reverse2,app(app(cons,x),xs)),l) -> app(app(reverse2,xs),app(app(cons,x),l))
        app(hd,app(app(cons,x),xs)) -> x
        app(tl,app(app(cons,x),xs)) -> xs
        last -> app(app(compose,hd),reverse)
        init -> app(app(compose,reverse),app(app(compose,tl),reverse))
        
)