I had an onsite interview after a simple phone interview. There were 5 rounds of interviews on the onsite day, including lunch.

• Going deep into my projects
• Coding

Lunch

• Culture fit (behavioral questions with the manager)
• System design
• Object-Oriented Design (OOD) and coding

I was rejected 5 days after the interview. Since I thought I performed well, I asked the recruiter twice about my weaknesses during the interview so I could improve next time. However, the recruiter never replied to my emails. This was a bad experience.

Why do you choose Uber?

Input a list of arrays: [[1, 2, 3], [1], [1, 2]]. Return a list of arrays, where each array is a combination of one element from each input array.

Example output: [[1, 1, 1], [1, 1, 2], [2, 1, 1], [2, 1, 2], [3, 1, 1], [3, 1, 2]]

Follow-up: Each array in the input list is an iterator, which can only be looped once.