If the area of a rectangular region is equal to the area of a square, then the perimeter of the rectangular must be
Brain Station 23
| Founding year | 2006 |
| Company Website | http://www.brainstation-23.com/ |
| Career Website | https://erp.bs-23.com/jobs |
| Technologies Used | Android, IOS, React, React-Native, Odoo, Xamarin, .Net, PHP, Python, Java, AEM, Sitecore, Flutter |
Introduction
Brain Station 23 is at the forefront of global digital transformation, delivering state-of-the-art technology solutions designed to propel businesses into the future. With expertise spanning software development, cloud computing, enterprise-grade mobile applications, AI and machine learning, and blockchain technology, they offer bespoke solutions that drive innovation and efficiency.
Star Coder Interview Stages
Star Coder is an annual recruitment test for BS23. The program has 5 stages
Online MCQ Exam: Everyone who applies for the program will be given the opportunity to sit for this round. Questions are asked from computer science subjects. The topics generally cover programming, data-algo, OOP, databases, etc. Those who do well in this exam are shortlisted for the next step.
Onsite Exam: This round is onsite, a 2-3 hour written exam. Candidates have to take an online exam on problem solving, data algorithms, databases, etc. No internet access is given for this stage.
Day long Assessment Test: This is an interesting round. There are various events throughout the day. Teamwork, idea generation, fun, etc. It is a lot like a hackathon. Presentations have to be given. It takes place in their office from morning to evening. Candidates are given a scenario and some questions. They have to come up with a solution and present it. The submissions are ERD, wireframe, SQL etc.
Technical Interview: Candidates may be interviewed about the project they developed in Step 3. They may also be asked about problem solving and computer science fundamentals
HR Interview
Client Facing Interview: Sometimes candidates are tasked to conduct a real client facing interview. This stage is not applicable for everyone and only given occasionally.
The information presented here is collected from the LinkedIn post of Abdullah Al Hasan vaiya (with his permission, of course).
Online MCQ Round
The problems presented in this round are fairly basic. The format is multiple choice.
Topics Covered are:
- Object-Oriented Programming (OOP)
- Database
- Data Structure & Algorithm
- Problem-Solving
- Output Tracing
- Analytical Ability
- Software Development Life Cycle (SDLC)
The questions provided here are collected from various online platforms such as Facebook and Glassdoor. No individual candidate has disclosed the questions verbatim.
Mr. Joy is planning to build a web browser. Now he is analyzing requirements for the navigation system of his web browser, which will preserve the browsing history. What is the appropriate data structure to use for the navigation system?
In the following code snippet, what does the keyword 'this' refer to
java
class Employee {
private String name;
public Employee(String name) {
this.name = name;
}
}In a bag , there is black and red balls. The ratio of black to red is 3:7 , if we add 20 more black balls to the bag then the ratio becomes 1:2. How many red balls are there?
which of the following is false about RDBMS (Relational Database Management System)?
- RDBMS supports concurrency control to handle multiple transactions simultaneously.
- RDBMS uses tables to store data in rows and columns.
- In RDBMS, a unique constraint prevents null values in a column.
- RDBMS ensures data integrity using ACID properties.
A train leaves station A at 7 AM with the speed of 60 kmph, and another train leaves the A station at 8 AM with the speed of 90 kmph..when will the second train catch the first train?
What will be the output of the following code?
cpp
#include <stdio.h>
int main() {
int sum = 7 + 6 / 3 + 14 * 2;
printf("%d", sum);
return 0;
}In the context of the Software Development Life Cycle (SDLC), which model emphasizes the continuous iteration of the development and testing phases throughout the project, accommodating changes in requirements even late in the development process?
Who is most likely to write unit tests in a software development project?
Once upon a time, a group of detectives were presented with a challenge to identify which of the 1000 candies was poisoned before it caused harm to any living species. They had to act fast, as the poison would take effect within an hour of consumption. The detectives knew they could use test subjects, but they needed to determine the minimum number required to solve the mystery in time. Can you help them find the solution before it's too late?
In the Agile Model, what is the primary purpose of a "sprint"?
What does the static keyword mean when used with a method?
Why are immutable objects often preferred in OOP design?
You are given an undirected graph with weighted edges. Which algorithm would you use to find the Minimum Spanning Tree (MST)?
What is the time complexity of searching for an element in a balanced binary search tree?
There are 100 light bulbs and 100 people. Initially, all bulbs are off. Person 1 flips every bulb (1, 2, 3, 4, …). Person 2 flips every 2nd bulb (2, 4, 6, …). Person 3 flips every 3rd bulb (3, 6, 9, …), and so on, until all 100 people have acted. How many people would have flipped bulb number 72?
A circular queue has a size of 5 and currently contains 3 elements. How many more elements can you insert?
You are given the head of a circular singly linked list and an integer n. How would you remove the nth node from the end of the list efficiently?
You are working with a binary search tree (BST) and need to find the lowest common ancestor (LCA) of two nodes, u and v. Which of the following is the most efficient approach for finding the LCA in a BST, assuming no additional balancing is applied?
What is the next term in the series: 1, 4, 9, 16, 25, __?
In a many-to-many relationship between two database tables, which of the following is typically used to model the relationship?
Given a code, you have to determine which OOP features is not used in the code above?
Which of the option in a given list is NOT a valid SQL data type?
Given a list of statements, which of them is false for dynamic programming?
A game development team is working on a character system where all characters have a fight() method. Characters like Warrior, Mage, and Archer implement this method differently. Which concept ensures the correct method is executed based on the character type?
Given a list of situations, In which of them would a stack be most appropriate?
In a network of cities and roads, you are given n cities and m roads between them. Your task is to determine the minimum number of new roads required to ensure that there is a path between every pair of cities. What is the most suitable approach to solve this problem?
Given a graph in figure, What is the shortest path from a point A to point F using BFS?
Given a list of examples, which of them is an example of compile-time polymorphism?
You are given a list of n unique room numbers belonging to guests at a hotel. These numbers are in the range [0, n], but one guest's room number is missing from the list. What is the best possible space complexity for solving this problem?
Identify the What type of casting is demonstrated in a code segment?
Given some figures of graph, identify which is not a bipartite graph?
What is the purpose of the final keyword in OOP?
Write a SQL query to retrieve the names of all customers who have placed an order with a total value greater than $1000. Orders are in the orders table and customer information is in the customers table.
Given some statements about database keys, which of them is incorrect?
Onsite Coding Round
This round is a mixture of coding problems and MCQs. The topics are the same as the online MCQ round. On average, the number of coding problems given are 9-10 and the number of MCQs are around 30.
Given a number n, write a program to reverse the digits of the number.
Given a number n, write a program to find if the number is an armstrong number or not.
An Armstrong number is a number that is equal to the sum of its digits, each raised to the power of the number of digits in the number. For example, 153 is an Armstrong number because 1^3+5^3+3^3=153
Write a program to print a string by removing
- leading, trailing space,
- if there's two or more space between two chars replace it with one space.
Write a program which will do the following for i = 1 to N .
- if i is divisible by 3 then print 'Star',
- if i is divisible by 5 'Coder'
- if i is divisible by 3 and 5 both print 'StarCoder'
- else just print the number
Given an integer array nums, rotate the array to the right by k steps, where k is non-negative.
Given a number n, print its factorial i.e. n!
Given an unsorted array of integers nums, return the length of the longest consecutive elements sequence.:
Ex: Input: 5 3 2 1 After Sort: 1 2 3 5 Ans: 3
Bonus: Write an algorithm that runs in O(n) time.
Given two integers N (upto 18 digits) and M(≤100): Digits of the New Number:
- The new number should be formed by permuting the digits of N.
- The new number must not have any leading zeros.
- The new number must be divisible by M. find the num of numbers that match these conditions.
Input: 104 2
Output: 3
→104, 140, 410Day long Assessment Test
Candidates need to stay in the office from morning to evening. They are presented with multiple tasks throughout the day. Most important of them are
- Written Exam
- Project Planning and Presentation
- Interview
Written Exam
The written exam have 3 segments
- Behavioural Test
- Aptitude Test
- Technical Test
It is taken first thing in the morning. Some of them are taken in sheet of papers and some are taken in external or internal websites.
Behavioural Test
The behavioural tests are quite similar to the ones standardized by Amazon. The situational judgment test (SJT) or behavioral assessment stage evaluates a candidate's decision-making and problem-solving skills in workplace scenarios. Candidates are presented with a situation and two possible responses, selecting their preference on a scale from strongly favoring one option to neutral or favoring the other. This helps employers assess traits like leadership, teamwork, and customer focus. Companies like Amazon use this method to identify candidates who align with their core values and work culture.
A customer reaches out with a complaint about a product they purchased. They are clearly frustrated, but the issue falls outside the company’s usual return policy.
A customer reaches out with a complaint about a product they purchased. They are clearly frustrated, but the issue falls outside the company’s usual return policy.
You and a coworker are working on a project together. They propose an approach that you don’t fully agree with, but they seem confident it will work.
Aptitude Test
Aptitude tests assess a candidate’s problem-solving ability, logical reasoning, numerical skills, and verbal comprehension. These tests are commonly used in hiring to evaluate a candidate's ability to think critically and process information efficiently. They are often timed and include questions on math, logic, patterns, and language. These tests are written or MCQ type questions. On average there are 30 questions like these.
If you had to choose 1 food to eat for the rest of your life, then what would it be? why?
Which actor do you like the most? why?
When do you feel sad the most?
Technical Test
This test is language dependent. You'll be asked to chose a language eg Java, JavaScript, Python etc and the questions will be based on that language. There are about 15 questions in this test.
The topics are from core language features, loop, time complexity, data structures, algorithm etc.
Give a description about your favourite project
Project Planning and Presentation
One of the tasks is to come up with a solution for a given scenario. The candidates are divided into groups and each group is assigned a mentor. The mentor will guide the group throughout the task. The groups need to present their solution at the end of the day. The presentation includes ERD, wireframe, SQL etc. Each one of the group members needs to present a part of the solution.
Create presentations on a ticket management system
Each team is given a big presentation paper. They will need to present the whole system within that paper.
Individual Interview
Each candidate faces yet another interview at the end of the day. This stage is language independent and focues on general software development knowledges. Topics might include git, SDLC, data structures, algorithm etc.
Some situations are given, you'll need to provide which algoritm is best suited for solving the task.
Given some code, you'll need to figure out the time complexity of the code
Project Submission
This round is not present in the Star Coder program every year. But in some years, candidates are asked to submit a project. A scenario is given to the candidates through email. The project is chosen based on the candidates preferences presented in the previous rounds. The project is to be submitted within a week. The projects given are pretty basic, but the candidates are expected to follow best practices.
A sample project scenario is given below:
Create a simple system for a task management system.
Technical Round
This round is also language and stack specific. The language is chosen by the candidate during the day long assessment. Some sample questions from Java are given.
What is primitive and non primitive data types? How are they different? When can their values be changed?
Why are strings immutable in Java?
What are the 4 principles of OOP?
What is diamond problem?
Does Java support multiple inheritence?
How does Java tackle the multiple inheritence issue?
What features of Spring Boot have you used?
What is indexing in Database?
Describe ACID in RDBMS
Some questions might be asked from the projects added in resume. If github repository links are added then interviewer might check those out too.
Suppose you have to build a e-commerce site where you have multiple product listing. In the home page the products have some small information listed. When you click on any single product then full details of the product is shown. How would you design the database and system for this?