L3 | Google | Chances

Had my Google L3 phone screen (~45 mins) and wanted some honest feedback on my chances of moving to onsite.

Interview

Started with 2-3 questions about AI usage in coding - when I use AI-generated code, when I don't, and how I verify it. I answered that I mainly use it for boilerplate, repetitive tasks, documentation, and navigating large codebases/logs, but don't blindly rely on it for architectural decisions.

Coding

Given N points, count the number of squares, including rotated squares.

I initially gave an O(N^4) brute-force solution.

I then optimized it to O(N^2) time and O(N^2) space using the midpoint of every pair of points and grouping pairs that could be diagonals.

The interviewer then said there was a function available which, given two diagonal points, returns the other two points, and explicitly told me to take this as a hint.

Using that, I implemented the simpler O(N^2) solution with a set of input points and checking whether the returned points exist. I also handled double-counting.

Follow-ups

Duplicate points: She asked whether the given function would solve the duplicate-point case. I said no, because the function returns coordinates but doesn't preserve frequency/multiplicity. We'd need to maintain frequencies if duplicate points count separately.

Rhombus: She then changed the problem to counting rhombi. I said I would use the diagonal properties/perpendicularity, but I couldn't fully derive the complete solution before the interview ended.

My question

Assuming the phone screen is around Lean Hire / borderline Hire, and my separate Googleyness round is Hire, how would you assess my chances of moving to onsite?

Please be honest, especially about how much the interviewer giving the optimization as a hint and not fully solving the rhombus follow-up would hurt.