Microsoft Sr. Software Engineer interview questions

Three rounds in total. First round feels like a tech screening, check if you can code. I was asked to implement a LinkedList and find a way to check if the LinkedList contains a loop. The second round feels a bit like system design, I need to write some pseudocode to implement a Google Drive like system. The last round is a difficult leetcode problem. During each interview they ask you some behavioural questions too. There are long waiting period between each interview. For me it took at least 1 week for recruiter to get back, and another 1 week to schedule the next interview. After the last interview it took 3 weeks before the recruiter got back to me.