Perforce Software Principal Software Engineer interview questions

It was through a referral that i had applied. HR called me and scheduled round 1 with Hiring Manager. He did the Hiring Manager questions for checking fit for 15mins and then started off with Technical questions where he gave me a code and asked about design pattern. Plus some questions regarding Caching strategies. Later i understood he was not from the department i was being hired for. I passed that round and was in Round 2. In round 2 a very experienced guy, but very humble and cooperative. He threw a backtracking problem in my plate, and i was struggling unfortunately couldn't solve it. Over experience was great for interview, it was good learning.