(VAR f x xs y z )
(RULES 
        app(app(h,z),app(e,x)) -> app(app(h,app(c,z)),app(app(d,z),x))
        app(app(d,z),app(app(g,0),0)) -> app(e,0)
        app(app(d,z),app(app(g,x),y)) -> app(app(g,app(e,x)),app(app(d,z),y))
        app(app(d,app(c,z)),app(app(g,app(app(g,x),y)),0)) -> app(app(g,app(app(d,app(c,z)),app(app(g,x),y))),app(app(d,z),app(app(g,x),y)))
        app(app(g,app(e,x)),app(e,y)) -> app(e,app(app(g,x),y))
        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(filter,f),nil) -> nil
        app(app(filter,f),app(app(cons,x),xs)) -> app(app(app(app(filter2,app(f,x)),f),x),xs)
        app(app(app(app(filter2,true),f),x),xs) -> app(app(cons,x),app(app(filter,f),xs))
        app(app(app(app(filter2,false),f),x),xs) -> app(app(filter,f),xs)
        
)