Buyhatke

Role: FTE (Full-Time Employee)

College: Not Specified (Campus Placement)

Interview Date: August 1, 2019

Interview Type: On-Campus/Full-Time

Result: Rejected

Difficulty: Medium to Hard

Rounds: 3 rounds

Topics Asked: Data Structures (Binary Search Trees, Trees, Linked Lists), Algorithms (Catalan Numbers, Next Greater Number, Substring Count, Merge Intervals, Quadruples, Nodes at distance K, Box Stacking), Operating Systems (Process, Thread, Thrashing, Deadlock, Priority Inversion), System Design (Elevator System), Android Development, Problem Solving (Compound Words).

Experience:

The selection process started with CV shortlisting, followed by three rounds.

Round 1 (Coding Round): This round was conducted on Interviewbit.com and comprised 4 coding questions, which were described as "fairly simple":

• Merge a given interval into a list of intervals.
• Find unique quadruples that sum up to a target value.
• Find all nodes at a distance of k from a given target node.
• Box stacking problem.

15 candidates were selected for the next rounds.

Round 2 (Skype Interview): This round began with a discussion about the candidate's resume, schooling, and internship experience.

Operating System questions included:

• What is a process and a thread? What is the difference between the two?
• What do you mean by thrashing?
• What is deadlock and what are the necessary conditions for deadlock? What is the way to prevent a deadlock?
• What is priority inversion and what is the solution to it?

Data Structures and Algorithms questions involved:

• What is the number of binary search trees that can be made from a given sorted array of unique numbers? (Catalan number).
• Given an inorder and preorder traversal of a binary tree, write code to print the tree, if a unique tree can be identified.
• Write code to find the next greater number with the same set of digits as that of a given number (e.g., for 4132, make 4213).
• Given a character 'c' and a string 's', find the number of substrings that have the character 'c' present only once in them.

Candidates were asked to write running code on codeshare for these questions.

Round 3 (CEO Round): This round was taken by the CEO, Gaurav Dahake, interviewing 7 candidates simultaneously over Skype textual chat. Questions included:

• Design and code an efficient elevator system.
• A question about reading WhatsApp messages from another application and sending a sample APK.
• Given a dictionary, find a list of all compound words (e.g., moonlight = moon + light).

The candidate found this round very tiring, lasting 8 hours, and ultimately received a rejection.