I was contacted by a recruiter who saw my LinkedIn profile.

My initial experience involved a very brief phone screen with an HR representative.

About a week later, I had a technical phone interview with a Google engineer. He called approximately seven minutes late and had a very strong accent. The connection was poor, and he did not seem focused on the interview, as I could hear Facebook messages coming through in the background.

He also presented several concepts incorrectly. For instance, he initially referred to a list of numbers as a set, implying no repetitions, but later changed his mind to simply a list.

Although I eventually arrived at the correct answer, it took the entire duration of the phone call, and I believe there was another question he intended to ask. Furthermore, he did not grant me the promised seven extra minutes at the end and repeatedly reminded me that time was nearly up.

A few days later, my recruiter called to inform me that they had decided not to proceed with my application. She provided no useful feedback and did not solicit nor seem to value my input.

Overall, I found the experience to be quite unprofessional and will likely refrain from interviewing with Google again.

Find the difference between two unsorted sets (lists).

An interviewer eventually revealed that they wanted a solution in O(n) time.