Interview Experience at AIHIFusion Technologies Pvt Ltd (Celeb AI) – Delhi NCR, India

Hello Leetcode Community,

I hope you all are doing great and enjoying your journey!

I am a 2024 B.Tech graduate from a tier-3 college with 6 months of internship experience at a small service-based startup.

I applied for AIHIFusion Technologies Pvt Ltd (Celeb AI) through a LinkedIn post where they mentioned an email. I sent my resume via email at the end of February or the beginning of March. They offered a salary of 4-5 LPA with a 1-year bond.

After around 15-20 days, the hiring process started. Many candidates, including me, were invited to a Zoom video call, where the company introduced itself. They then conducted an aptitude test with 30 questions, requiring a cutoff of 15 or 18 marks to qualify.

My Interview Rounds:
✅ Aptitude Test: Passed
✅ Technical Round 1: Passed (held on the same day)
✅ Technical Round 2: Passed
⏳ Technical Round 3: Appeared but likely failed

Interview Experience:
All rounds were conducted online. Each technical round started with a short introduction, followed by C++ or Python OOPs concept questions (depending on your choice).

They focused heavily on OOPs concepts in every round, asking in-depth questions on C++, OOPs, and DSA, such as:

• Implement a function similar to erase in set in C++ without memory leaks
• Static functions, static classes
• Overriding with and without virtual functions and their differences
• Why virtual functions?
• Why use namespaces in C++?
• Why use std::? If we use std, why do we still need libraries?
• Why or why not use const and global variables?
• Implementing recursion inside a class
• Implementing linked lists
• Writing code without STL
• Finding duplicate elements in a given array in constant space
• OOPs basic concepts
• Some more questions I can't remember

Technical Round 3 - The Toughest One
They asked:
💬 "You are given a container that stores values in sorted order upon insertion. What data structure does it use, and what is its time complexity?"
➡️ I answered: In C++, it's a set, which uses a balanced binary search tree (BST).

Then they asked me to implement an erase function similar to erase in set, where:

• I am given the head of a tree and a value to delete.
• After deletion, the container must remain sorted, just like in a set, where deleting any value maintains the sorted order.

I attempted it, but after some back and forth, they clarified that "delete" meant deleting the node without memory leaks. At this point, I struggled, as I had never implemented such deep C++ code beyond solving DSA problems.

Final Thoughts:
I believe I am going to be rejected. But I wonder—for a fresher, is it reasonable to ask for such detailed C++ implementations (like manually re-implementing set::erase(), ensuring no memory leaks) when the salary is just 4-5 LPA with a 1-year bond?

I didn’t have any issues with the other questions, but I felt this one was particularly difficult due to the need to handle things like memory management and avoiding leaks.