I had a phone interview with a recruiter, followed by two technical interviews. Honestly, the interview wasn't difficult. I felt I performed quite well, answering three questions with relative ease. There were follow-up questions, which I also handled adequately. However, I was rejected.

I'm unsure of the reason and frustrated by the lack of explanation recruiters often provide. While the process was fairly quick, it's disappointing to not know why I didn't advance to the next round.

Flatten an array (got follow-up questions)

Convert Roman numeral (string format) to sum

Includes/excludes array question (you can find the complete questions on the forum)