I applied online. The process took 2 weeks. I interviewed at Two Sigma (London, England) in Oct 2017
Interview
Applied through their website. Got an email the next day offering a HackerRank test. Then phone call with a recruiter, and on-sites scheduled the next week. On-sites lasted from 9am to 6pm, with a succession of 1 hour rounds, and a lunch with part of the team in the middle.
The questions were interesting and challenging, everybody was nice and smart – interviewers were helpful and it felt like they wanted me to succeed. The whole experience was very pleasant. Got a phone call from the recruiter congratulating me and telling me they would extend an offer. Offer came a week later.
Interview questions [1]
Question 1
HackerRank 3 hour online test – one question boiled down to a BFS, the other was a dynamic programming problem. The whole thing was easily solvable in less than 45 minutes.
first interview was 60 minutes long with a leetcode hard question. second interview was 2 back to back 60 minute leetcode hard with emphasis on data structures. each interview had a 5 minute introduction and 10 minute at the end to ask questions
Standard medium difficulty hackerrank. The question involved decoded an encoded string. It was not something I had seen on LeetCode before and I think was unique to the company. The question was not that difficult but I ran out of time right before I could finish answering.
Interview questions [1]
Question 1
Decode a string encoded using a specific encoding algorithm.
It started of with one phone screen, then if you pass you have 2 back to back technicals, then 3 1 hour behaviorals, hiring committee, and management committee. Standard Leetcode and behavioral questions.