I had five rounds of interviews.

The first round was a gatekeeper round, which I cleared to get into a full-day interview process (which had at least four rounds).

The interviews were primarily technical, focusing on algorithms and data structures.

The difficulty level of the interviews increased, and steeply at times.

The first three rounds were simpler, while the last two rounds were more difficult and focused on mapping out the individual's strengths and weaknesses. (I got through the first four rounds but did not clear the last one).

The interviewers were open to giving hints and helping candidates solve problems.

Apart from the solution itself, a positive approach, openness to reconsider, and thoughtful problem-solving were also important aspects.

Preparing for the interview with online questions helps, but the interview experience is truly new. The level of questions can easily be adjusted, so preparation is beneficial, but it's important to stay calm and think through the problems during the interview.

I also felt that candidates need to demonstrate enjoyment of the problem-solving process and confidence in their ability to solve them effectively. Interviewers were also keen on accurate self-assessment.

What is the lowest time complexity algorithm for finding all combinations of numbers a, b, and c in an array of integers such that c² = a² + b²?