'Coding has over 700 languages', '67% of programming jobs aren’t in the technology industry', 'Coding is behind almost everything that is powered by electricity'
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SDE - 2
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6 rounds | 13 Coding problems
Interview preparation journey
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Preparation
Duration: 3 months
Topics: DataStructures , Algorithms, System Design,Big Data,Spark,Optimization
Tip
Tip

Tip 1 : Be solid with the basics of Ds, Algo. Good to have end to end projects which are hosted on cloud/Github.
Tip 2 : Its always good to be presentable and have good communications skills
Tip 3 : Be honest, clear in approach and always walkthrough your thought process to the interviewer, If you dont know something kindly refuse , dont try to fake anything

Application process
Where: Linkedin
Eligibility: 2+ years of Experience in relevant field/team
Resume Tip
Resume tip

Tip 1 : Mention your projects and experience at the top. Be clear on what was done, a brief on how it was done, language /tech stack involved. If possible try to host and make it accessible. You never know if you can present it with just one click.
Tip 2 : Choose a balance between, white spaces and text, it should be well indented, no grammatical errors.
Tip 3 : It takes less than 2 min to scan a resume. Don't mention things which are irrelevant.

Interview rounds
01
Round
Medium
Video Call
Duration90 Minutes
Interview date5 Jan 2021
Coding problem3

It was a zoom call with a SDE-2 person, after 15 mins into my background he jumped directly to the questions
 

1. Binary Tree Zigzag Traversal
Easy
15m average time
85% success
0/40
Asked in companies
Expedia GroupDelhiveryPayU

You have been given a Binary Tree of 'N' nodes, where the nodes have integer values. Your task is to print the zigzag traversal of the given tree.

Note:
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2. Convert binary tree to mirror tree
Easy
15m average time
85% success
0/40
Asked in companies
Phone PeSamsungDunzo

Given a binary tree, convert this binary tree into its mirror tree.

A binary tree is a tree in which each parent node has at most two children.

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3. Time to Burn Tree
Hard
50m average time
50% success
0/120
Asked in companies
AmazonThalesMicrosoft

You have a binary tree of 'N' unique nodes and a Start node from where the tree will start to b...

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02
Round
Medium
Video Call
Duration90 Minutes
Interview date7 Jan 2021
Coding problem2

Again this was a Problem Solving round taken by a SDE-2 

1. Technical Questions

Started off by asking Java Fundamentals, OOPS,DesignPatters(Singleton,Factory,Cascade), HashMap Internals,Collections, Fail Fast-Fail Safe Iterators
Then jumped off to Problem Solving - Egg Dropping Problem
 

2. Topological Sort
Moderate
30m average time
70% success
0/80
Asked in companies
SprinklrSamsungAmazon

A Directed Acyclic Graph (DAG) is a directed graph that contains no cycles.

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03
Round
Hard
Video Call
Duration100 Minutes
Interview date12 Jan 2021
Coding problem2

This round was with a SDE-3(Principal Engineer)

1. Technical Questions

He took a deep dive into my resume and asked a lot of questions around my projects asking my roles and responsibilities in each project/product/team. Asked about Kadane's Algorithm.
After that he started with Spark Theory based questions, MapReduce Concepts in deep,Shuffle internals,Questions on Hive ,repartition,MSCK repair tables, RDDs,Catalyst optimizer,Lineage Graph,SparkDrive,Spark Subm...

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2. Trailing Zeros in Factorial
Moderate
15m average time
80% success
0/80
Asked in companies
Tata 1mgGoldman SachsUber

You are given an integer N, you need to find the number of trailing zeroes in N! (N factorial).

Note:

1. Trailing zeros in a number can be defined as the number of cont...
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04
Round
Hard
Video Call
Duration90 Minutes
Interview date18 Jan 2021
Coding problem1

This round was scheduled with a SDE-3/SDE-4(Senior Principal Engineer):
He directly started with questions after my introduction of 5mins
 

1. Technical Questions

Question 1 : A scenario/story where Bitonic Sequence was to be implemented.
Question 2 : Design a Scheduler for scheduling n jobs with input give at the runtime , input can be the also generic service to be called.
Question 3 : Assuming you are dumping data in-memory via a data-pipeline , Design a garbage collector that will remove unsed data.(I gave and explained Mark and sweep...

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05
Round
Medium
Video Call
Duration90 Miinutes
Interview date20 Jan 2021
Coding problem3

Discussion with Hiring Manager
 

1. Basic HR Questions

My Aspirations, Problems I have solved, How do I motivate myself, Disappointment faced, Situations where your solution was accepted other than your peers and How did you convince the management for this, Hardest Situation Overcome in Life(I gave My weight transformation from 110 to 60 kg, he did not believe it so showed Facebook Picture)

2. Technical Questions

Deep-Discussion on my projects , My Approach on there use cases /or the problem they were facing , Questions on Spark(Broadcast Join Scenario), Questions on Mapreduce (Scenario Based)
Question on String Pool, String Buffer internals, Multi-threading, Concurrency

3. Loot Houses
Moderate
26m average time
0/80
Asked in companies
Dell TechnologiesShopeeQualcomm

A thief wants to loot houses. He knows the amount of money in each house. He cannot loot two consecutive houses. Find the maximum amount of money he can loot.

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06
Round
Easy
Video Call
Duration75 Minutes
Interview date22 Jan 2021
Coding problem2

This round was with VP in Redwood City , it was scheduled around 11:00 pm IST
 

1. Basic HR Questions

Manager Relationships, Difficult problem solved, Normal day routine, How do I manage a stressful situaiton, Leadership skills, Why I want to join there company, What will happen If I get rejected from this stage, My Life Aspiraitons

2. Technical Questions

Discussion on my resume, Work exp, Team Size, Duration of Projects, Counter Question: Why did you switch 2 companies with your experience and why do you want to switch and come here(Despite my answer he advised me to be patient and wait for opportunities).
Discussion on OS, Semaphores,Mutexes,Case Scenarios, Locks 
Locking In Distributed Env(1 Phase Vs 2 Phase VS 3 Phase Commits), Sp...

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