I had a short initial call with HR where we discussed the next steps. HR informed me that the next round would focus on Data Structure and Algorithms coding skills and advised me to solve medium/hard LeetCode problems. The next round was scheduled for two weeks later, during which I dedicated my time to solving LeetCode problems.

During the coding interview, I encountered the most unprofessional interviewer I have ever met. He was distracted by his environment, struggled to maintain the conversation, and did not answer some of my questions. The coding challenge itself was not related to LeetCode at all; it was a task to write a memoization closure function. Unfortunately, I was completely unprepared for such a question. The first several minutes were spent on redundant clarifying questions, as I did not believe this was the task I was going to spend time on.

I did solve the task by the end of the interview, but it took too much time, and I was not selected for the subsequent rounds.

memoize is a function that takes one argument, asynchronousFunction:

javascript function memoize(asynchronousFunction) { }

where asynchronousFunction is a function that takes n arguments. The last argument of asynchronousFunction is a callback in the form of function callback(error, result).