UnitedHealth Group Software Developer interview questions

The first round was a web cam monitored aptitude and coding test for a total duration of ~ 2 hours. The aptitude was of moderate difficulty and the coding questions were very easy(hardly took 10-12 minutes for both the questions). Then there were 2 TRs and 1 HR round scheduled. I was called in for my first interview round at around 4:00 PM. This last round lasted for around 1.25 hrs. The interview began with a system design question (which I was not expecting). i tried my best to do it and the interviewer also pointed some things that i was missing while drawing the UML. We had a discussion on it for around 30 mins Then he asked me some SQL queries. They were easy but the last one was quite hard. He again gave me a slight hint and i somehow managed to then do it. Then he asked me a question on circular linked list but he was looking for the most optimal answer. I managed to solve it using the rabbit and tortoise approach(the question was not middle of linked list).Then he asked me about my projects and the reason behind their topic and technology used. Then he asked me about my current internship and what if they offer me PPO. Then he asked me about my weakness and why i want to join Optum. Finally the interview ended and I was asked to wait outside while he wrote my feedback...After 15 mins, to my surprise, I was directly sent to the HR round..!! It was such a relief to see the HR xD...Anyway she asked some normal questions and it lasted for around 20 mins...It was a very chill round. I was asked about my current offers and why I am not joining those companies... Lastly she shook my hand and told me "congratulations you have succesfully completed the interview process at optum.The waiting period and the technical grilling i had undergone was worth it" :P I have received a written confirmation (mail) from them and am awaiting the salary breakup and offer letter.