What is OOD/LLD Round?
OOD/LLD Round is a technical interview that evaluates a candidate's knowledge and understanding of software design and architecture. It is typically part of the interview process for Software Engineering positions and aims to assess the candidate's ability to design and implement complex software systems.
The OOD (Object Oriented Design) round of a software engineering interview assesses a candidate's comprehension of OOD concepts, principles, and practices. This evaluation encompasses the candidate's understanding of design patterns, SOLID principles, and UML (Unified Modeling Language). The interviewer will assess the candidate's practical experience in designing and executing software systems and ability to effectively communicate their design decisions and thought processes.
On the other hand, the LLD (Low-Level Design) round focuses on evaluating the candidate's capacity to decompose complex problems into smaller, more manageable components and implement these components in code. The interviewer will inquire about the candidate's experience working with data structures, algorithms, and coding practices. They will also assess the candidate's knowledge of techniques to optimize performance, handle errors, and debug software.
During an OOD/LLD (Object Oriented Design/Low-Level Design) round, the interviewer evaluates the candidate's software design and architecture knowledge and skills. This can involve questioning the candidate about specific design patterns and their experience in creating systems from scratch. The interviewer may also request the candidate to demonstrate their understanding and implementation of key concepts and principles by writing code on a whiteboard or computer.
How to Prepare for the OLD/LLD Round?
Preparation is key to success in any interview, especially regarding the technical aspects of software engineering.
Here are some tips to help you prepare for an OOD/LLD round:
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Brush up on your design patterns: Design patterns are reusable solutions to common design problems. Familiarize yourself with the most commonly used design patterns, such as the Singleton, Factory, and Observer patterns.
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Study SOLID principles: SOLID is a set of design principles for writing maintainable and scalable software. Understanding the SOLID principles, such as Single Responsibility, Open/Closed, Liskov Substitution, Interface Segregation, and Dependency Inversion, will show your interviewer that you have a strong foundation in software design.
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Get familiar with UML: UML is a visual language that describes and visualizes software systems. Brush up on your UML skills, and be prepared to use it to explain your design decisions and thought process.
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Practice coding: Practicing your coding skills is essential, especially when it comes to implementing design patterns and solving algorithmic problems. Work on small projects that involve designing and implementing systems.
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Read books and articles: Read books and articles on software design and architecture to stay updated on the latest trends and practices in the field. Some recommended books include "Design Patterns: Elements of Reusable Object-Oriented Software" by the Gang of Four and "Clean Architecture" by Robert Martin.
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Join online forums and discussion groups: Participating in online forums and discussion groups related to software design and architecture will help you stay updated on the latest trends and best practices. It will also allow you to interact with other software engineers and ask questions.
- Practice coding under pressure: Writing code under pressure is an essential skill in software engineering. Practice writing code on a whiteboard or a computer during timed exercises to get used to the pressure of the interview setting.