Infosys Interview Experience for Power Programmer 2021 (Virtual)

Infosys conducted HackWithInfy, a coding competition for 2022 engineering students graduating across India. Only one Round of coding tests was conducted this year in May 2021. The results came out in June 2021 and I had the opportunity to appear for a Power Programmer interview.

The interview was scheduled for July 22, 2021, at 9:00 AM and was a one-hour-long interview. 

The interview joined the meeting at 9:03 AM, then:

Interviewer:  Hi ${myName}

Me: Hello Sir.

Interviewer: Am I taking your name correctly?

Me: Yes Sir.

Interviewer: So ${myName}, the interview will be divided into two parts, first the coding round, followed by a technical discussion.

 Me: *nodding my head

Interviewer: There is a library, that sells books and gives a discount on the price……..

Me:  Sorry sir for interrupting. Can I write down the question ?? (I was not ready for  it, I thought based on all the interview experience I have read, the interview generally  starts with “introduce yourself” or “tell me  about your skillset”, etc..)

Interviewer: Sure, share your screen and use any editor

Me: Shared my screen and used VSCode as my editor.

Interviewer: Continued with the question.  (The question was similar to Sliding Window Maximum (Maximum of all subarrays of size k) from GFG).

Me:  Thinking (once mentioned Heap while thinking) Asked few questions related to the problem, then again Thinking(for 5min). Then gave him the Brute Force Solution with time complexity O(n*k).

Interviewer:  Write the code and use any language of your choice.

Me: Wrote the code in Python.

Interviewer: Why did you disregard the heap idea?

Me: Gave him the reason.

Interviewer: Ok. Let us move to the second question.  Given a palindrome number find the next smallest palindrome.

Me: Told him my approach.

Interviewer: Gave some test cases.

 Me: Dry run my approach on those test cases.

Interviewer: Tell one of your projects and some difficulties that you have faced.

(the discussion went for 7 to 10 minutes)

Interviewer: Have you worked on any databases?

Me: Yes sir. I have worked on NoSql databases (MongoDb).

Interviewer: Why NoSql?? Why not a traditional SQL database?

Me: Told him my requirement and how NoSql was solving my problem.

Interviewer: Give me some disadvantages of NoSql over SQL?

Me: Told him about the disadvantage (I have mention normalization in my answer)

Interviewer: As you have mentioned normalization. What is normalization? Can you explain with example?

Me: Gave him the definition. And Discussed all the steps with examples.

Interviewer: Do you know about OS?

Me: Yes Sir.

Interviewer: Oh you are a CSE student, you have Operating System in your academics. Am I right?

Me: Yes, Sir.

Interviewer: There are two processes (A and B). B is reading a file and process A wants to access the same file. How will OS handle this case?

Me: Told him about Semaphores. 

Interviewer: As you have mentioned NodeJs in your resume, tell me some technical differences between NodeJs and Java.

Me: (I have nothing related to Java in my resume nor do code in Java)  Mentioned about the NodeJs community, NPM. 

Interviewer: (Mentioned about the Java community and told me about Maven) Give me some technical differences.

Me: Mention to him how NodeJs does the async operation Javascript being single-threaded. Describe how the event loop works in detail.

Interviewer: As you know how NodeJs internally works. Can you give me the output of the code?

Javascript

let a = new Promise(resolve => {
    console.log(1);
});

a.then(_ => console.log(2));

Me: Again Thinking

Interviewer: Just say what you think then we will discuss.

Me: 

1
2

(Again Thinking)

Interviewer: Run the code.

VS Code:

1

Me:  Ohh. The promise is not getting resolved.

Interview: Now give me the output for this.

Javascript

let a = new Promise(resolve => {
    console.log(1);
    setTimeout(() => {
        resolve();
    }, 3000);

});
console.log("Hello")
a.then(_ => console.log(2));

Me: Thinking

1
Hello
2 (After 3sec)

Interviewer: Run the code

VS Code:

1
Hello
2 (After 3sec)

Interviewer: (Smile) Do you have any questions for me?

Me:  Asked for some feedback.

Interviewer: Gave the feedback. And told me it’s good to know the fundamentals and how things work.

(Followed by some other general discussion and some HR questions) then

Interviewer: Nice talking to you.

Me: Thank you for your time, sir.