HashedIn

Role: Software Engineer

College: Not Specified

Interview Date: May 29, 2021

Interview Type: Off-Campus (Referral)

Result: Selected (implied as recruiter called for next interview, and no rejection mentioned after HR)

Difficulty: Medium-Hard

Rounds: 3 rounds

Topics Asked: DSA (Maximum Product Subarray, Word Search - recursive/Trie), Web Technologies (DOM vs Virtual DOM, REST API path/query params), OOPs (Runtime/Compile-time polymorphism, Dynamic dispatching), Data Structures (Hashtable vs Hashmap), DBMS (Indexing), Version Control (Git merge vs rebase), System Design (Shorten URL, Auto-suggestion using Trie).

Experience:

This candidate received a referral for a Software Engineer role.

Round 1 (Coding Round): Duration was 1 hour, with 2 questions of Medium difficulty.

• Question 1: Maximum Product Subarray. The candidate solved it with some struggle but no hints.
• Question 2: Word Search. The candidate came up with a recursive approach and tried to use a Trie, but due to time constraints, the interviewer asked for the recursive code.

The result of this round was positive, and the recruiter scheduled the next interview.

Round 2 (Technical Interview - Coding & Conceptual): Duration was 1 hour, with a focus area of 15% coding (design type) and 85% conceptual questions. The difficulty was Medium-Hard. A lot of questions were asked, including:

• Difference between actual DOM and virtual DOM.
• Write code for runtime and compile-time polymorphism.
• Difference between hashtable and hashmap.
• What is indexing in a database table.
• What is path param and query param in REST API.
• What is dynamic dispatching in OOPs.
• Difference between git merge and git rebase.
• System Design: Shorten URL (convert 3000 characters to 7 characters).
• System Design: Auto-suggestion for a search box given dictionary words (Trie approach, with follow-ups on handling very long dictionary words). The candidate was unable to answer the follow-up questions.

HR Round: Duration was 30 minutes, with general questions.