I received a call directly from Zscaler HR. They explained the position, and within two days, they arranged the first round of interviews. Due to COVID-19, the entire process was conducted on Zoom. I completed four rounds.

In each round, they asked two to three questions. The questions were related to C programming, such as:

• extern, volatile, static functions and variables
• Trees
• Bitmaps (4-5 questions)
• Arrays
• Strings
• Linked lists
• Stacks
• Projects I had completed

I performed well in the first three rounds. In the fourth round, I got stuck on a small problem, but the interviewer helped me write the code, which I did. However, the interview result was negative, and it has been almost three months since they last informed me.

There are billions of numbers streaming in. How would you identify if a number has already appeared? Write neat, clean, and modular code. Although you have to write on Wordpad.

A stream of bits is coming. After finishing the stream, find out if the incoming stream was a power of 4.