I received a call from HR about a job opening. She told me that if I answered three questions correctly, it would be the first screening process. She asked some bookish questions about data structures that I had forgotten since my engineering days ten years ago. I was able to answer one correctly out of three. She said that I am good in Java, but not good in data structures. All this happened within the span of ten minutes. So, I think I am never going to apply again, as I was not able to last even the first ten minutes of an HR call.

What is the time complexity of a certain data structure collection?

I can't recall which one.