The interviewer was multitasking while he was interviewing me, and well he was doing it effortlessly.
He began by saying it will be a 1 hr interview, with first 45 minutes for DSA and last 15 minutes for HR questions, he then began without asking for an intro, and pasted the question to the doc.
I was able to come up with a solution within time, so I briefly explained it to him, he asked me to code it up after clarifying/understanding my approach.
After I was done, he gave another follow-up, which I gave multiple approaches to, but not the one he expected. However, he appreciated that I tried approaching in multiple ways. And he asked some common HR questions the last 15 mins, and the interview ended successfully!