...Which means if a user go to the URL www.website.com/ask-question/, then it will redirect them to login page www.website.com/login/?next=/ask-question/.
The best way to go is to modify your server code so that when a user who isn't logged in (including search engine robots) tries to access www.website.com/ask-question/, the returned HTTP code will be 301 (which means moved permanently) and the location in the header will become www.website.com/login/?next=/ask-question/.
To verify if you constructed your redirect properly, go to https://redbot.org and enter http://www.website.com/ask-question/ and the first 11 characters in the black box that appears should be the following if your server uses HTTP 1.x:
Then somewhere in that box, you should see a line that starts with "Location:" with "http://www.website.com/login/?next=/ask-question/"
Change "http://" to "https://" in all cases if all webpages on your server use SSL (which most seem to do these days).
The advantage to this is that just about any web browser will transparently handle the redirect for you so the end user will think that only one page is loaded. Also, Search engines never index pages that return the HTTP 301 status code as they offer no value. And third, if a user decides to bookmark the page, then only one easy URL will represent the page.