There was an online interview via video call that lasted for 1 hour. I was given one question, which I solved and then optimized four times.

My onsite interview was scheduled for one month later. It consisted of four coding questions and one behavioral interview. I solved all the coding questions.

However, I was not selected. The feedback stated that there was not much usage of data structures and that I took too much time, indicating less time efficiency.

1st Online Phone Screen Interview:

Given an array A of length N (from A[0] to A[N-1]). Each element A[i] can only be a 0 or 1. If a sub-array only contains 0s, we call it valid. How many valid sub-arrays are there in A?

For example, if A = [0, 0, 1, 0, 0, 0], there are 9 valid sub-arrays.

2nd Onsite Interview:

Q1. Data streaming of infinite users: find the top 5 most active users. Given a WhatsApp group where people are chatting, find who uses the maximum number of words.

Q2. Robot finding a path in a grid from top-left to bottom-right, avoiding obstacles. Given a grid of a terrain for a robot to traverse from one corner to the opposite corner. Find the path, or determine if a path is even possible. The grid is 10x10 or NxN. Each square defines the height or depth of the square.

Q3. Finding the difference between two satellite images of the same place taken one month apart.

Q4. String and tree problems.