Zillow Software Development Engineer, interview questions

I had applied online and also contacted the HR via email. The HR replied asking me to start on with the process Step 1: Take home coding challenge - the same 2 questions that Zillow asks everyone I completed this in 4 days Step 2: Phone interview - general discussion on my previous projects - find all pairs that add up to a certain value in an array Step 3: Skype interview - general discussion on my previous projects - find lowest common ancestor Step 4: Onsite - 4 technical rounds on whiteboard with different team members. The code that you write needs to be perfectly compilable. Over all my experience was great. The HR was very quick to follow up and I completed my process very fast. Amazing office in downtown Seattle, with a great view from the 34th floor. The interviews were very helpful and always carried a happy face.