The phone screen was a video call phone screen interview, spanning for 45 minutes.
First 5 minutes were introductory, about myself, what i currently do and all that.
https://leetcode.com/problems/merge-k-sorted-lists/ But with arrays, instead of linked lists.
I Spoke about the brute force approach, then discussed a solution using a heap. He agreed with the heap solution and I proceeded to code it out. While testing, discovered some bugs involving indexes and figured them out. Took a few minutes to debug and small hint from the interviewer to discover the bug. Interviewer was satisfied and I pointed out a separated edge case that we both hadn’t considered. I coded out a fix for that edge case ( just an if statement ).
Gave the right time and space complexities for the solution and he agreed.
In Total, Took about 20 minutes
I Spoke about the brute force approach, n^3 but we both knew that was too slow then we spoke about an n^2 solution using a hashtable and he asked me to code it out.
After coding it out, we had about 6 minutes left but I still brought up a potential sliding window solution with O(N) runtime. He asked me to discuss how I would implement this and i did this. He seemed satisfied and we ended the problem.
The last 6 minutes were just me asking questions about his work and facebook and why he works for FB.