Perguntas de entrevista de vagas de Senior Full Stack Developer da empresa Definity First

I had 3 technical interviews one of them was a theorical interview with different Big O problems were I was asked to give a time and space complexity, even though the recruiter told me the team just wanted to know me, needless to say I was expecting more work/team related questions. The last interview was a coding challenge very Microsoft/Facebook like, very complicated were one needs to know about algorithms/data structures and also provide time and space complexity. I was not expecting this kind of questions, mainly because this company doesn't even offer law benefits, you're practically a freelancer, if I were prepared for an interview like this I would be applying to a big tech company.