1. He asked me a DS question for which I gave and wrote the solution in 7-8 minutes only.
2. Later he asked out some NodeJs and Javascript questions all of which I answered immediately and explained to him well.
He wrapped up the interview in 15 min, after taking the slot for 1 hour.
It seemed like the engineer was himself not in the mood of taking the interview seriously and it was totally a waste of time for me.