Expedia Group Software Development Engineer In Test SDET II interview questions

Received a call from HR of Expedia, who has seen my profile in LinkedIn. He asked me couple of simple questions like what is Hashmap and a question about finding combination of numbers in an array that add up to a certain value. I got three rounds of telephonic interviews scheduled after a week or two. Then I was asked to fly to Expedia in Gurgaon. I had three rounds of interview. The questions are not tough, I could write code for all the questions, however, based on the feedback, the code wasn't optimized enough.