When I was a first year computer science undergraduate at University of York, I bumped into Sir Tony Hoare at the bus stop outside Ron Cooke Hub in Heslington East campus the day before I learnt quicksort.

I have never heard of him before. He was complaining about the bus being late. He looked like a learned scholar, considering that we were not far away from the Department of Computer Science, I said to him that the bus arrival time is Poisson distributed, as bus arrives at a constant rate, and each arrival is independent to each other. He agreed with me. I asked him if he is a lecturer or professor in a university, he told me that he is a researcher who works in Cambridge. (It turned out that he worked for Microsoft Research at that point.) I asked him how he knew about Poisson distribution, he replied that he learned a bit of statistics when he was in university. (It turned out that he studied some sort of postgraduate statistics in University of Oxford.) His friend later asked me if I knew about Hoare's logic, I replied that I did not. His friend asked me which year I was in, I told him I was a first year undergrad. His friend then asked me if I knew quicksort, I replied that I did. He told me that the old learned scholar standing next to us was Sir Tony Hoare, the inventor of quicksort. It was quite an interesting experience - way better than bumping into a celebrity.

Anyway, for quite a while, I joked that the best pick-up line would be a discussion about Poisson distribution. You end up talking to really intellectual people.

Dr Jeremy Jacob (https://www.cs.york.ac.uk/people/jeremy) discussed the origin of quicksort with me right before I left York. He told me that Sir Tony Hoare's wife might have come up with quicksort, or at least she gave a lot of help to Sir Tony Hoare. However, she didn't want to take the credit. Jeremy's PhD supervisor was Sir Tony Hoare. Please treat the origin story of quicksort as apocrypha. I will amend this story, if Jeremy or Sir Tony Hoare ever contact me about it.