I applied online. The process took 3 weeks. I interviewed at Jane Street (Hong Kong) in Oct 2014
Interview
I had 3 rounds of Telephone Interview. The first two were from HK offices, the last one was from London. The first interviewer was very nice, quickly introduced himself and asked me a programming question and I had to write the solution on a shared screen. The interview lasted 45 mins and the question had 3 variants of increasing complexity. The second interviewer did not speak English all that well, asked me about simple questions about my resume and another programming task in similar settings. Unfortunately, the website we were using for sharing our screens went down in the middle of the interview and I had to send him my solution via email. The third round also followed a similar format.
Interview questions [3]
Question 1
First round: Given two linked lists of integers, how to find the length of the smallest list? Followed up by how do I find the list with the smallest sum.
Third round: Given an array with a heap property, how do I insert and delete elements into the heap while maintaining the heap property. Followed up by, how to recursively delete the entire subtree.
It was a very quick and painless process. Recruiter very responsive, kind interviewers. High implementation and difficult problems, so failed onsite after 3 interviews and a Question and Answer Session.
Did not pass the initial coding round. I tried to explain my thought in details to the interviewer but failed to translate my thought into code. So far interviewer is very nice.
I applied online. I interviewed at Jane Street (New York, NY)
Interview
My experience interviewing at Jane Street was definitely challenging, but also surprisingly collaborative. Instead of focusing only on whether I could get the right answer quickly, the interviewers were much more interested in how I approached problems and explained my thinking. I worked through a few coding questions involving data structures and algorithms, and there were also some probability-style questions that tested logical reasoning. The interviewers were clearly very sharp, but they were also approachable and encouraged me to talk through my thought process the entire time. When I got stuck, they would sometimes guide me with small hints so we could keep exploring the problem together. Overall, it felt less like a typical high-pressure interview and more like a thoughtful technical conversation with experienced engineers.
Interview questions [1]
Question 1
“What is the expected number of coin flips needed to get two heads in a row?”