Google

The level is OK, not too hard but not too easy. Actually, I was expecting much more challenging questions. The only problem is that they give you only a partial description, so you need to communicate with the interviewer to get more info. I did it

Long, multistep process. Online screening with sample tasks, followed by a whole day in-person with approximately 5 developers. Online screening conversation with HR, sample tasks, and lengthy conversations with developers.

The interview was tough. It consisted of data structures and algorithms. Google, or companies like Google, mainly focus on problem-solving skills. If you can solve problems, then you are in.