I applied through a staffing agency. The process took 2 weeks. I interviewed at Two Sigma (New York, NY) in Aug 2015
Interview
The company has employees from Google, Facebook and Microsoft. They are the top sponsors of TopCoder and other Math competitions. Employees are super smart, maybe smarter than top tech companies. It is definitely the first finance company, although its a technology company, in which Engineers are a first class citizen.
Screen: Hacker Rank Coding Round - 2 hard problems
Phone Interview: All technical questions including a coding problem
Onsite: 6 rounds + 1 Lunch ( 4 coding + 2 technical discussions and design)
The problems were similar in complexity as Google or Microsoft, kicker is that you code on the computer instead of a whiteboard.
Interview questions [4]
Question 1
Bitwise Operation, Add one to a number without using +
Given a phone keypad and Knight(Chess), find out if you can form a phone number using all the possible moves of the Knight, if you can then return all the possible phone numbers as a list of string.
e.g. The Knight moves in an L shape in any direction. We can say that it either moves two squares sideways and then one square up or down e.t.c
Find out all the possible numbers, digits in the number can repeat.
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.