Is it possible to use the same URL, but with different dynamic segments? 

My issue is: I want to be able add object `A` to objects `B` and `C`. So I want to have 2 Rails routes, `A/new/:b_id` AND `A/new/:c_id`. Which I tried.

In my routes.rb:

```
controller :A do
  get 'A/new/:b_id', to: 'A#new', as: :new_b_a
  get 'A/new/:c_id', to: 'A#new', as: :new_c_a 
end

```

Problem is that the value being passed into the new page is always `params[:b_id]`! (I can print out the value from the URL using `params[:b_id]`.)

So it seems like maybe I can't have 2 similar routes with different dynamic segments..? If so, how would I do this?