My first interview was with HackerRank. I read a Medium article from Coinbase about their interview process, which mentioned they rank code quality, including documentation and readability, above the optimal solution. Therefore, I spent time focusing on those aspects.

The interviewer seemed very bored toward the end of the interview. When I mentioned I could run the code now, he responded, "Oh, you've written it." He then looked at what I had written and said, "Oh yes," which led me to believe he hadn't been paying close attention. The code passed and ran correctly. I had added documentation and classes everywhere and verbalized my assumptions for different aspects. The interviewer seemed fine with it.

At the end, I asked questions about the company, and he suddenly showed interest, which indicated a shift in his tone throughout the interview.

TLDR; I solved the question and made my code as clean as possible, but I still didn't get through. He was also late to the call.

Given two lists of buy orders and sell orders, respectively, match the buy orders with existing sell orders for a certain item.