Interview Experience at AIHIFusion Technologies Pvt Ltd (Celeb AI) – Delhi NCR, India
Summary
I am a 2024 B.Tech graduate with 6 months of internship experience who interviewed for AIHIFusion Technologies Pvt Ltd (Celeb AI) in Delhi NCR. I successfully passed the aptitude test and the first two technical rounds, but struggled significantly and likely failed the third round, which heavily focused on in-depth C++ OOPs concepts and manual data structure implementation, particularly memory management in a set-like erase function.
Full Experience
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.
Interview Questions (12)
Implement C++ Set Erase Function without Memory Leaks
Implement a function similar to erase in std::set in C++, ensuring no memory leaks. This involves deleting a node from a balanced binary search tree while maintaining its sorted order and proper memory management.
C++ Static Functions and Classes
Explain C++ static functions and static classes, including their purpose and usage.
C++ Overriding with Virtual Functions
Explain method overriding in C++ with and without virtual functions, detailing their differences and implications.
Purpose of C++ Virtual Functions
Explain the purpose and benefits of using virtual functions in C++.
C++ Namespaces
Explain the purpose and benefits of using namespaces in C++.
C++ std Namespace vs. Libraries
Explain the use of std:: namespace in C++ and differentiate between the std namespace and broader C++ libraries.
C++ const and Global Variables
Discuss the pros and cons, and appropriate usage of the const keyword and global variables in C++.
Implementing Recursion within a C++ Class
Explain how to implement recursive functions within a C++ class.
Implement a Linked List
Implement a basic linked list data structure in C++.
Coding without C++ STL
Discuss or demonstrate writing C++ code without relying on the Standard Template Library (STL).
Find Duplicate Elements in Array (Constant Space)
Given an array, find duplicate elements using constant extra space.
Sorted Container Data Structure
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?