Interesting question, but it was rejected.

I received this email reply:

"We want to thank you for the time and effort you have put into our HackerRank challenge. At Stripe, we are meticulous about our foundations and have a very specific set of skills that we are targeting for our university program. For this reason, our engineering team takes the time to review coding challenges after HackerRank’s initial grading.

Unfortunately, after reviewing your submission, we have decided not to move forward with your candidacy at this time.

While we weren’t a mutual fit right now, we were impressed with your coding challenge responses and want to encourage you to keep an eye on our jobs page for any openings in the future that you might be interested in. Due to the number of applications we receive, we are unable to accommodate multiple HackerRank challenge submissions within a single season."

Not data structures or algorithms, but more to what they do on Stripe.