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Role: SDE-1

College: Not Specified (University Student)

Interview Date: On-Campus Virtual 2020 (Post dated July 2025, experience refers to 2020)

Interview Type: On-Campus Virtual, Full-Time

Result: Selected

Difficulty: Medium

Rounds: 4 rounds (Online Round, 3 Technical Rounds, 1 Hiring Manager Round)

Topics Asked: Data Structures, Algorithms, Computer Science Core Subjects, OOPs, DBMS, System Design, Projects, Internships

Experience:

The process started with an online round for around 800 eligible students.

Online Round: Conducted on HackerRank. It had 15 MCQs (technical + aptitude) and one coding question.

• Coding Question: "Maximum amongst minimum in sub arrays". An optimal solution using the heap concept (NlogN) was required.

Around 40 students were selected for the next round.

Round 2: Elimination Round (Coding Test on paper) - 13 students were selected from this round.

• Question 1: "Minimum no. of coin to a given amount". The candidate used a dynamic programming solution.
• Question 2: "Longest palindromic subsequence in string". The candidate used a dynamic programming solution.

Round 3: Technical F2F - Two interviewers were present. After an introduction, they reviewed the resume and code.

• Explanation of Round 2 code, and discussion of alternative solutions (e.g., greedy for coin problem).
• Favorite subjects (Data Structures and Algorithms) were discussed.
• Scenario-based questions on sorting algorithms (which to use, why, worst-case).
• Database questions: ER diagram design and SQL queries (group by, having, subquery) for a given problem.
• OOPs concepts: Difference between encapsulation and data hiding, accessing private data from other classes.
• Other technical questions involved HashMap vs HashTable, Load balancing, Horizontal and vertical scaling.
• Coding questions included:
  • Given a binary tree and a number, return true if the tree has a root-to-leaf path such that adding up all the values along the path equals the given number.
  • Modification of the above: print all such paths if they exist.
  • Print the middle element in a Singly linked list in a single traversal only.
  • Implement HashMap in Java with an interface class as Map and implement a method for hashCode.

Round 4: Technical F2F - This round involved discussing online test experience and preferred programming language (C++).

• Virtual function implementation in a compiler.
• Real-life examples for OOPs concepts.
• Data Structures: Add functionality to find maximum in a stack in O(1).
• Delete a node (given node pointer) in a linked list if no head pointer is given.
• The interviewer also asked about internship work and projects. The candidate demonstrated their Web+Machine Learning project, which impressed the interviewer.

The company selected 4 candidates.

Way of Preparation: GeeksforGeeks, LeetCode, InterviewBit, HackerEarth.

Overall Experience: The interview process was smooth, and interviewers were friendly. Communication with the interviewer and explanation of code were crucial.

General Tips: Be calm and prepare well for DSA, OS, Networking, DBMS, System Design, OOPs concepts, and know your resume very well.