Trilogy Innovations Interview Experience by Sahil Marwaha | Off Campus - Aug 2021

New update is available. Click here to update.

Trilogy Innovations interview experience Real time questions & tips from candidates to crack your interview

SDE - Intern

Trilogy Innovations

6 rounds | 8 Coding problems

Sahil Marwaha

Fresher | Aug 2021

Rejected

Interview preparation journey

Journey

I started in my 3rd year and solved more than 1500 questions on various coding platforms such as Leetcode, and geeks for geeks, participated and practice questions on CodeChef. Created more than 30 projects on react JS, and Node JS. Also made projects on Blockchain. When started my placement journey in the collage I cracked 6 on campus and 4 off-campus placements.

Application story

I asked for a referral from an SDE-2 working in the company using LinkedIn, after a week I received a call from HR and he gave me an coding test that I need to complete in given time. After that there were multiple interview rounds.

Why selected/rejected for the role?

The basic reason for my selection was my strong knowledge of core subjects and basic fundamentals and my problem-solving ability.

Preparation

Duration: 2 Months

Topics: Competitive Programming, Dynamic Programming, Trees and Graphs, Quants, Vocab

Tip

Tip 1 : Practice competitive programming.The level of questions asked in the programming round is pretty high.
Tip 2 : Have 1 project you know inside and out.

Application process

Where: Other

Eligibility: None

Resume tip

Tip 1 : Make sure you really know everything about any project you put on your resume. They will pick up anything from there randomly and grill you on it.
Tip 2 : Highlight what you learnt from your projects.

Interview rounds

Round

Easy

Online Coding Test

Duration120 Minutes

Interview date1 Aug 2021

Problems3

This was an online coding round with 3 questions. It was held in the evening. The level of questions was pretty high. I don't remember all the problems now, but there was one graphs, one on dp, and one on combinatorics. One thing I would suggest is to be well versed with graphs, trees and DP. In all the rounds of theirs I have seen, these topics are always asked.

1. Ways To Make Coin Change

You are given an infinite supply of coins of each of denominations D = {D0, D1, D2, D3, ...... Dn-1}. You need to figure out the total number ...

Try solving now

2. Ninja And The New Year Guests

Ninja has organized the new year party and invited all the programmers for it, as being the programmer also has been invited by Ninja.

Try solving now

3. Bipartite Graph

Given an undirected graph of ‘V’ vertices (labeled 0,1,..., V-1) and ‘E’ edges . Your task is to check whether the graph is bipartite or not.

A biparti...

Try solving now

Round

Hard

Online Coding Interview

Duration15 Minutes

Interview date1 Oct 2022

Problems0

There are 50 questions, based on English, logic and maths. The test is for 15 minutes, and the cutoff is 45. The logic and maths questions were pretty easy, but I practiced GRE words for the English section. You can take this test anytime in the window they provide (it was a few weeks), and you get 2 attempts.

Round

Medium

Telephonic

Duration30 minutes

Interview date1 Nov 2021

Problems0

This was a telephonic resume round. It was in the evening. The interviewer asked me to choose any one project or internship from my resume, and then proceeded to grill me on it. He asked me about why I used the technologies that I did for the project, and then about certain improvements that could be made to the project and how I would go about them.

Round

Medium

Video Call

Duration60 Minutes

Interview date2 Nov 2021

Problems2

This was the DSA round, in which I was given 2 questions to solve. It was in the afternoon. The interviewer was really encouraging, and helped me a little when I got stuck on the 2nd question.

1. Maximum Subarray Sum

You are given an array 'arr' of length 'n', consisting of integers.

Problem approach

I was already familiar with Kadane's Algorithm. This problem was a slight modification of that. First, I set up the basic code for Kadane's algorithm, and then I created a dp[n][2] array. Here, dp[i][0] stores the largest subarray sum up to that index (basic Kadane's algorithm), and dp[i][1] stores the highest subarray sum up to that index, given you have squared one element somewhere till that...

Try solving now

2. Square Submatrix with sum less than or equal to K

Given a 2-dimensional matrix of size ‘N’ x ‘M’ and an integer K. Find the size of the largest square sub-matrix whose sum is less than or equal to K. The size of a matrix is the product...

Problem approach

My first approach was brute force. I created a 2d-prefix sum array for the given matrix, and then iterate over all possible squares in this matrix. For each square, I checked if the sum was <=k, and stored the highest size of all such squares.
I was stuck for a bit here, and didn't know how to optimise this further. After a small hint from the interviewer, I came up with the solution. Fix...

Try solving now

Round

Medium

Video Call

Duration60 Minutes

Interview date3 Nov 2021

Problems2

This was an open ended discussion round. It was held in the afternoon. First, the interviewer asked me about an internship I done earlier, and asked me to code an algorithm for a problem related to that. After that, he asked me an open ended question, and we discussed about optimising the solution as well.

1. System Design Question

When users scroll social media, the often miss some posts when they are scrolling quickly. How will you ensure that the posts they scrolled past too fast will show up again in an infinite scroll? I was asked to code an algorithm for this as well. My approach was to listen for scroll events and measure the time that each post was on the screen for. I was also asked how I would persist this data ...

Problem approach

Tip 1 : Think about the larger picture, not only how you will perform the particular task, but about what changes you will need in other places to accommodate this.

2. System Design Question

Design a text compressor for Google Docs. I went with Huffman Encoding, since I had done a project on it earlier. I needed to optimise this for changes made in the middle of the document. The approach was to split the document into smaller parts, and encode each one independently.

Problem approach

Tip 1 : I would recommend checking out Gaurav Sen on YouTube. The level of the question was not as high, but you'll get a better idea on how to approach these questions.

Round

Easy

HR Round

Duration15 Minutes

Interview date4 May 2022

Problems1

This was an HR round with the CEO. He was really nice, and asked basic questions.

1. Basic HR Questions

Why I wanted to join the company, and why I would be a good fit.

Was this interview experience helpful?