Boston Scientific Principal Engineer Interview Questions and Answers

Stack using queues: push() - enqueue to queue1, pop() - dequeue from queue2 after transferring n-1 elements from queue1 to queue2

• To push an element, enqueue it to queue1

• To pop an element, transfer n-1 elements from queue1 to queue2, dequeue the last element from queue1 and swap the names of queue1 and queue2

• Queue using stacks: enqueue() - push to stack1, dequeue() - pop from stack2 after transferring all elements from ...read more

Doubly linked list is a data structure where each node has a pointer to both previous and next nodes.

• Create a Node class with data, prev and next pointers

• Create a LinkedList class with head and tail pointers

• Implement methods to add, remove and traverse nodes

Yes, I am a leader.

• I have experience leading teams in previous projects.

• I am able to communicate effectively and motivate team members.

• I am proactive in identifying and solving problems.

• I am able to delegate tasks and trust team members to complete them.

• I am constantly seeking to improve my leadership skills through learning and feedback.

Area of square except inscribed circle

• Find area of square

• Subtract area of circle from square

• Area of square = L^2, Area of circle = pi*(L/2)^2

• Answer = L^2 - pi*(L/2)^2

A program to find factorial using recursion.

• Define a function that takes an integer as input.

• Check if the input is 0 or 1, return 1 in that case.

• Otherwise, call the function recursively with input-1 and multiply it with the input.

Indexes are data structures that improve the speed of data retrieval operations in a database. Views are virtual tables created from queries.

• Indexes are used to quickly locate data in a database by creating a sorted structure that allows for efficient searching.

• Views are virtual tables that are created by executing a query and storing the result set as a named object.

• Indexes can be created on one or more columns of a t...read more

Indexes are implemented using B Trees and B+ Trees.

• B Trees and B+ Trees are data structures used to organize and efficiently search data in databases.

• B Trees are balanced search trees that store data in nodes with multiple children.

• B+ Trees are similar to B Trees but have additional features like leaf nodes that form a linked list.

• Indexes are created on specific columns of a database table to improve query performance.

• ...read more

Other than indexes and tables, a DBMS also includes views, stored procedures, triggers, and functions.

• Views: Virtual tables that are based on the result of a query. They provide a way to simplify complex queries and restrict access to data.

• Stored Procedures: Precompiled sets of SQL statements that can be executed with a single command. They enhance performance and allow for code reusability.

• Triggers: Special types of s...read more

A database administrator manages and maintains databases, ensuring their security, performance, and availability.

• Designing and implementing database structures

• Installing and configuring database software

• Monitoring and optimizing database performance

• Ensuring data integrity and security

• Backing up and restoring databases

• Troubleshooting and resolving database issues

• Collaborating with developers and system administrators

• Pla...read more

Types of integrity in DBMS include foreign, referential, and domain.

• Foreign integrity ensures that foreign key values in a table match primary key values in another table.

• Referential integrity ensures that relationships between tables are maintained, preventing orphaned or invalid data.

• Domain integrity ensures that data in a column adheres to specified data types, formats, or constraints.

• For example, in a database for ...read more

SDLC is a process followed by software development teams to design, develop and test high-quality software.

• SDLC stands for Software Development Life Cycle

• It consists of several phases including planning, analysis, design, implementation, testing, and maintenance

• Each phase has its own set of activities and deliverables

• The goal of SDLC is to produce high-quality software that meets customer requirements and is delivered ...read more

Agile methodology is an iterative and incremental approach to software development.

• Agile methodology emphasizes collaboration, flexibility, and customer satisfaction.

• It involves breaking down the project into small, manageable tasks called user stories.

• Teams work in short iterations called sprints, typically 1-4 weeks long.

• Regular meetings like daily stand-ups and sprint reviews are held to track progress and gather fe...read more

In 3-5 years, I see myself as a senior software engineer leading a team of developers on innovative projects.

• Advancing to a senior software engineer role

• Leading a team of developers on projects

• Working on innovative and challenging projects

• Continuing to learn and grow in the field

I am a passionate software engineer with experience in developing web applications using various technologies.

• Experienced in full-stack web development

• Proficient in languages such as JavaScript, Python, and Java

• Familiar with frameworks like React, Node.js, and Django

• Strong problem-solving skills and ability to work in a team

• Completed projects like e-commerce website using MERN stack

I want to learn how to play the piano.

• I have always been fascinated by music and the piano in particular.

• Learning to play an instrument can be a great way to relax and unwind.

• Playing the piano can also improve cognitive skills and memory.

• I believe learning to play the piano will bring me joy and fulfillment.

My strengths include problem-solving skills and attention to detail. My weaknesses include public speaking and time management.

• Strengths: problem-solving skills, attention to detail

• Weaknesses: public speaking, time management

Activity flow diagrams for Ola cabs management system and washing machine.

• Ola cabs management system: User books a cab -> Driver accepts the ride -> User gets picked up -> User reaches destination -> Payment is made.

• Washing machine: User selects wash cycle -> Machine fills with water -> Detergent is added -> Machine agitates clothes -> Water drains -> Clothes are rinsed -> Machine spins clothes -> Cycle ends.

Developed a web-based project management tool for a software development company.

• Used Agile methodology for development

• Implemented user authentication and authorization using JWT

• Integrated with GitHub for version control

• Used React for front-end and Node.js for back-end

• Implemented real-time chat feature using Socket.io

Reverse a number while preserving its sign.

• Extract the sign of the number using Math.sign()

• Reverse the absolute value of the number using string manipulation

• Convert the reversed string back to a number and multiply by the sign

Check if two strings are anagram

• Sort both strings and compare them

• Use a hash table to count the frequency of each character in both strings and compare the hash tables

• Use an array of size 26 to count the frequency of each letter in both strings and compare the arrays