The interview process involved three online tests, one Skype call, and one onsite interview in Tokyo, consisting of three 50-minute technical interviews each.

First, I was asked to take part in three online tests. I could take any of them, perhaps more than one, and achieve the best possible result. If the result was good enough, I moved on.

Next, I was invited to a Skype interview, which rarely rejected candidates except for those with very poor English skills.

Finally, I was invited to an onsite interview in Tokyo. Many candidates travel to Tokyo in batches, and I was interviewed with eight other candidates on the same day.

The onsite interview consisted of three technical interviews, each lasting 50 minutes with no long breaks in between. Each interview typically involved self-introductions from both the candidate and the interviewer, solving algorithm problems on a whiteboard, and a Q&A session. The time distribution was approximately 10 minutes for introductions, 35 minutes for problem-solving, and 5 minutes for Q&A.

I will not elaborate on the specific interview questions, but I believe the following advice is very helpful:

• Listen carefully and ask questions when a problem is ambiguous.
• Pay attention to the details the interviewer mentions; they might be helpful.
• Code quickly and explain your thought process clearly.
• Ask insightful questions when you have the opportunity.

The questions were not excessively difficult but required careful attention and optimization of memory and time efficiency to the utmost limit. The interviewers often posed problems with large data scales, demanding memory-efficient and fast algorithms.

I have to fill this part, but I've decided not to share the problem details.

Instead, I will share a really small question they asked in the process:

What's the largest value of an int in C++?