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

SDE - 1

Blackrock
upvote
share-icon
3 rounds | 5 Coding problems

Interview preparation journey

expand-icon
Preparation
Duration: 6 Months
Topics: Data Structures, OOPS concepts, Puzzles, graphs, Dynamic Programming and have good projects
Tip
Tip

Tip 1 : Practice DSA concepts regularly. e.g. trees, 2-pointer, linked list etc.
Tip 2 : Do 1-2 good projects in your college. Since the interviewer will be interested in that as it finally decides which team you will be joining. 
Tip 3 : Do prepare for puzzles and behavioral questions.

Application process
Where: Campus
Eligibility: 7 CGPA
Resume Tip
Resume tip

Tip 1 : In case you have more projects, mention the ones which you can explain well and are more confident in the tech stack used in the project etc.
Tip 2 : Mention the skills correctly since it will more or less decide the team you will be joining, so do not add unnecessary stuff.

Interview rounds

01
Round
Hard
Online Coding Interview
Duration60 Minutes
Interview date2 Sep 2019
Coding problem1

It was an online assessment round in morning.All the questions were MCQ type covering concepts of sql, oops, dbms, computer networks, code outputs , qualitative reasoning questions etc.

1. Output based Question

Determine the output of the given code snippets/ find error in the given code.

Problem approach

Go through the given code snippet, understand and dry run the code on different test cases.

02
Round
Hard
Face to Face
Duration60 Minutes
Interview date20 Sep 2019
Coding problem3

This round was a face-to-face interaction with the interviewers. This round had 2 interviewers.Questions were based on DSA, personal projects and puzzles.

1. Left View Of a Binary Tree

Easy
10m average time
90% success
0/40
Asked in companies
OlaHSBCArcesium

You have been given a binary tree of integers. You are supposed to find the left view of the binary tree. The left view of a binary tree is the set of all nodes that are visible when the binary tree is viewed from the left side.

Example:

example

The left view of the above binary tree is  {5, 7, 14, 25}.
Problem approach

1. I had solved the problem using a queue.
2. Interviewer asked me follow up questions related to other tree algorithms and if it could be used to solve the problem.
3. I was able to write complete solution for it and the interviewer was satisfied.

Try solving now

2. Row with Maximum 1's

Easy
10m average time
90% success
0/40
Asked in companies
ArcesiumDisney + HotstarMicrosoft

You have been given a non-empty grid ‘mat’ with 'n' rows and 'm' columns consisting of only 0s and 1s. All the rows are sorted in ascending order.

Your task is to find the index of the row with the maximum number of ones.

Note: If two rows have the same number of ones, consider the one with a smaller index. If there's no row with at least 1 zero, return -1.


Example:

Input: 'n' = 3, 'm' = 3, 'mat' = [[1, 1, 1], [0, 0, 1], [0, 0, 0]]

Output: 0

Explanation: The row with the maximum number of ones is 0 (0 - indexed).
Problem approach

1. Solved the problem using brute force approach
2. Interviewer asked me to optimize the solution.
3. Solved the problem using binary search and coded it.
4. Interviewer asked me to think of any better solution as well
5. Gave two pointer approach and discussed it. Did not ask to code this one.

Try solving now

3. Puzzle

There are 25 horses among which you need to find out the fastest 3 horses. You can conduct race among at most 5 to find out their relative speed. At no point you can find out the actual speed of the horse in a race. Find out the minimum no. of races which are required to get the top 3 horses. 

Problem approach

Tip 1: explained the solution using pen/paper and the interviewer was satisfied with the solution.

03
Round
Medium
HR Round
Duration30 Minutes
Interview date20 Sep 2019
Coding problem1

HR round with a lot of behavioral questions and questions about company.

1. Basic HR questions

Why do you want to join this company? 

Do you have other offers in hand?

 what do you know about the company ?

 and many other behavioral questions.

Problem approach

Tip 1: Read about the company's work culture before going for the interview.
Tip 2: Prepare behavioral questions.

Here's your problem of the day

Solving this problem will increase your chance to get selected in this company

Skill covered: Programming

How do you remove whitespace from the start of a string?

Choose another skill to practice
Similar interview experiences
SDE - 1
3 rounds | 2 problems
Interviewed by Blackrock
1070 views
0 comments
0 upvotes
SDE - 1
4 rounds | 5 problems
Interviewed by Blackrock
2170 views
0 comments
0 upvotes
SDE - 1
3 rounds | 3 problems
Interviewed by Blackrock
1555 views
0 comments
0 upvotes
SDE - 1
4 rounds | 9 problems
Interviewed by Blackrock
1267 views
0 comments
0 upvotes
Companies with similar interview experiences
company logo
SDE - 1
2 rounds | 3 problems
Interviewed by BNY Mellon
6365 views
3 comments
0 upvotes
company logo
SDE - 1
3 rounds | 6 problems
Interviewed by BNY Mellon
0 views
0 comments
0 upvotes
company logo
SDE - 1
3 rounds | 5 problems
Interviewed by CIS - Cyber Infrastructure
2197 views
0 comments
0 upvotes