11 Essential Coding Interview Questions + Coding Exercises! from Udemy

As you prepare for your next coding interview, have you ever thought:

"I wish someone could just walk me through these problems and explain what’s going on."
"I wish there was a preselected set of the most important coding interview problems so I can practice them easily."

If so, this course is for you.

In this course:

First, I’m going to give you a few problem solving techniques you’ll be able to use right away in your next coding interview.
Then, I’m going to walk you through the 11 essential coding interview questions and their answers.
I’ve picked these particular questions because they are the types of questions that are asked most often in programming interviews.
I’m going to cover problems that use concepts such as arrays, strings, two-dimensional arrays, linked lists and trees.
You’ll get a coding exercise in Python and Java for each problem, so you can get feedback on your solution right away.
If you want to use any other language to follow this course, that’s fine too. Just remember to run your solution on your computer to make sure it works.

This course is intended for intermediate to advanced learners who are preparing for their software engineer programming interviews.

So, I’m going to assume that you’re already familiar with concepts such as:

Two dimensional arrays (which are simply arrays of arrays)
Breadth first search and depth first search
Linked lists and trees

If you think you’re ready for this course, watch the preview videos and see if you can solve those problems.

What's inside

Learning objectives

Learn what a coding interview is like
Learn 3 problem solving techniques you'll be able to use in your next coding interview!

Go through 11 of the most essential coding interview questions, coding exercises and answers!
Overall, feel more confident and be ready for your next coding interview

Learn what a coding interview is like
Learn 3 problem solving techniques you'll be able to use in your next coding interview!
Go through 11 of the most essential coding interview questions, coding exercises and answers!
Overall, feel more confident and be ready for your next coding interview

Syllabus

Understand what the course is about and learn three handy problem solving techniques that you'll be able to use in your next coding interview!

Introduction

What Is a Typical Coding Interview Like?

Problem Solving Technique #1 for Coding Interviews

Problem Solving Technique #2 for Coding Interviews

Problem Solving Technique #3 for Coding Interviews

Be comfortable with coding interview questions that utilize arrays.

Most Frequently Occurring Item in an Array (Difficulty = *)

Most Frequently Occurring Item in an Array (Python)

Most Frequently Occurring Item in an Array (Java)

Most Frequently Occurring Item in an Array (Solution)

Common Elements in Two Sorted Arrays (Difficulty = **)

Common Elements in Two Sorted Arrays (Python)

Common Elements in Two Sorted Arrays (Java)

Common Elements in Two Sorted Arrays (Solution)

Is One Array a Rotation of Another? (Difficulty = **)

Is One Array a Rotation of Another? (Python)

Is One Array a Rotation of Another? (Java)

Is One Array a Rotation of Another? (Solution)

Be comfortable with coding interview questions that utilize strings.

Non-Repeating Character (Difficulty = **)

Non-Repeating Character (Python)

Non-Repeating Character (Java)

Non-Repeating Character (Solution)

One Away Strings (Difficulty = ***)

One Away Strings (Python)

One Away Strings (Java)

One Away Strings (Solution)

One Away Strings (Solution in Pseudocode)

Be comfortable with coding interview questions that utilize two-dimensional arrays.

Assign Numbers in Minesweeper (Difficulty = **)

Assign Numbers in Minesweeper (Python)

Assign Numbers in Minesweeper (Java)

Assign Numbers in Minesweeper (Solution)

Find Where to Expand in Minesweeper (Difficulty = ***)

Find Where to Expand in Minesweeper (Python)

Find Where to Expand in Minesweeper (Java)

Find Where to Expand in Minesweeper (Solution)

Find Where to Expand in Minesweeper (Solution in Pseudocode)

Rotating 2D Array (Difficulty = ***)

Rotating a 2D Array by 90 Degrees (Python)

Rotating a 2D Array by 90 Degrees (Java)

Rotating 2D Array (Out-of-Place Solution)

Rotating 2D Array (In-Place Solution)

Rotating 2D Array (In-Place Solution in Pseudocode)

Linked Lists and Trees

N-th Element of a Linked List (Difficulty = **)

N-th Element of a Linked List (Python)

N-th Element of a Linked List (Java)

N-th Element of a Linked List (Solution)

Is This a Binary Search Tree? (Difficulty = **)

Is This a Binary Search Tree? (Python)

Is This a Binary Search Tree? (Java)

Is This a Binary Search Tree? (Solution)

Is This a Binary Search Tree? (Solution in Pseudocode)

Lowest Common Ancestor (Difficulty = ***)

Lowest Common Ancestor (Python)

Lowest Common Ancestor (Java)

Lowest Common Ancestor (Solution)

Lowest Common Ancestor (Solution in Pseudocode)

Conclusion

Have any extra problems I should solve?

Good to know

Know what's good

, what to watch for

, and possible dealbreakers

Prepares students for the rigors of software engineering coding interviews

Provides hands-on exercises and solutions in Python and Java

Suitable for intermediate to advanced learners with prior knowledge of arrays, linked lists, trees, and other data structures

Covers essential coding interview problems and techniques

Enhances confidence and readiness for coding interviews

Reviews summary

Coding interview preparation

According to students, this course is a good resource for practicing coding interview questions and for learning about time complexity. However, learners report that some important information is missing from the videos and that more questions should be included.

The course only includes 11 questions.

"There should be more questions."

The course does not always explain the time complexity of its solutions.

"In the earlier video, you told us time complexity to obtain optimal solution."

"From later videos it's not there so we are unable to know whether this is optimal or should try for more before viewing your solution."

Activities

Be better prepared before your course. Deepen your understanding during and after it. Supplement your coursework and achieve mastery of the topics covered in 11 Essential Coding Interview Questions + Coding Exercises! with these activities:

Find a Coding Interview Mentor

Show steps

Seek out experienced professionals or senior students who have successfully navigated coding interviews to provide you with mentorship and guidance.

Browse courses on Problem Solving

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Reach out to your network or use online platforms to find potential mentors.
Schedule an introductory meeting to discuss your goals and expectations.

Watch YouTube Tutorials on Coding Interview Problems

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Watch video tutorials on popular coding interview problems to understand different approaches and solutions.

Browse courses on Arrays

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Find YouTube channels or websites that specialize in coding interview tutorials.
Choose a tutorial for a problem you're interested in.
Follow along with the tutorial and try to understand the solution.

Organize a Coding Interview Practice Group

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Join or start a study group to practice coding interview problems with other students and provide feedback.

Browse courses on Arrays

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Find classmates or online forums to connect with other students interested in coding interviews.
Set up regular meetings to practice solving problems together.
Take turns presenting solutions and providing feedback.

Five other activities

Expand to see all activities and additional details

Show all eight activities

Write Blog Posts on Coding Interview Tips

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Share your knowledge and insights on coding interviews by writing blog posts that provide tips and advice to other students.

Browse courses on Problem Solving

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Choose a specific topic related to coding interviews that you're knowledgeable about.
Write a well-structured blog post that covers the topic in a clear and concise manner.
Publish your blog post on a platform like Medium or Dev.to.

Practice Coding Interview Questions

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Solve coding interview questions to improve your problem-solving skills and prepare for your next coding interview.

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Identify a list of common coding interview questions.
Practice solving these questions on your own.
Review your solutions with a mentor or tutor.

Mentor Junior Students Preparing for Coding Interviews

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Share your knowledge and experience by mentoring junior students preparing for coding interviews, providing guidance and support.

Browse courses on Problem Solving

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Identify opportunities to mentor junior students through programs or online platforms.
Prepare materials and resources to help your mentees prepare for coding interviews.
Meet with your mentees regularly to provide guidance and feedback.

Contribute to Open Source Coding Interview Projects

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Contribute to open source projects on platforms like GitHub to gain experience working on real-world coding interview problems.

Browse courses on Data Structures

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Find open source coding interview projects on GitHub or other platforms.
Choose a project to contribute to and read the documentation.
Fix bugs, add features, or improve the documentation of the project.
Submit a pull request with your changes.

Build a Personal Coding Interview Project

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Develop a personal coding project that demonstrates your skills and knowledge in data structures, algorithms, and object-oriented design.

Browse courses on Data Structures

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Identify a problem or need that you can solve with a coding project.
Design the architecture of your project and choose appropriate data structures and algorithms.
Implement your project in a programming language of your choice.
Test and debug your project to ensure it meets the requirements.
Deploy your project and share it with others.

Career center

Learners who complete 11 Essential Coding Interview Questions + Coding Exercises! will develop knowledge and skills that may be useful to these careers:

Software Engineer

As a Software Engineer, you will design, build, maintain, and improve software systems that provide solutions to various business problems. This course can help you by teaching you essential coding interview questions that are frequently asked in SWE interviews, such as array manipulation, string manipulation, and problem-solving techniques. Having a strong understanding of these concepts will increase your chances of success in your next coding interview.

See salaries and explore the career path for Software Engineer

Full-Stack Developer

Full Stack Developers possess a comprehensive understanding of both frontend and backend development, enabling them to work on all aspects of web applications. This course will provide you with a well-rounded foundation in coding interview questions, covering a wide range of topics from data structures to algorithms and system design. By mastering these concepts, you can become a highly sought-after Full Stack Developer with the skills to tackle complex software projects.

See salaries and explore the career path for Full-Stack Developer

Software Architect

Software Architects design and oversee the development of complex software systems, ensuring their scalability, reliability, and performance. This course will provide you with a deep understanding of coding interview questions related to software design and system architecture. By mastering these concepts, you will be well-equipped to lead software development projects and create innovative and robust software solutions.

See salaries and explore the career path for Software Architect

Backend Developer

Backend Developers focus on the server-side of web applications, ensuring data integrity, handling database interactions, and building APIs. This course will provide you with a solid understanding of coding interview questions related to data structures, algorithms, and problem-solving. These concepts are crucial for developing efficient and scalable backend systems, enabling you to excel in your role as a Backend Developer.

See salaries and explore the career path for Backend Developer

Systems Analyst

Systems Analysts analyze, design, and implement computer systems to meet the needs of businesses and organizations. This course can provide you with a strong foundation in problem-solving techniques and system design, which are essential for success as a Systems Analyst. By understanding these concepts, you will be well-equipped to gather requirements, design optimal solutions, and ensure the efficient operation of computer systems.

See salaries and explore the career path for Systems Analyst

DevOps Engineer

DevOps Engineers bridge the gap between development and operations teams, ensuring seamless software delivery and maintenance. This course can provide you with a solid foundation in coding interview questions related to software engineering and system design. By developing a deep understanding of these concepts, you will be well-equipped to automate build and deployment processes, troubleshoot issues, and contribute to a high-performing DevOps team.

See salaries and explore the career path for DevOps Engineer

Computer Programmer

Computer Programmers translate designs and specifications into functional computer programs, creating the software that powers various systems. This course can help you develop essential coding skills and enhance your problem-solving abilities, which are crucial for success as a Computer Programmer. By mastering these concepts, you will be well-equipped to write efficient, reliable, and maintainable code.

See salaries and explore the career path for Computer Programmer

Data Scientist

Data Scientists leverage their expertise in statistics, machine learning, and programming to analyze data, discover patterns, and make predictions. This course will provide you with a solid foundation in problem-solving techniques, which are essential for success in data science. By learning how to approach and solve coding problems effectively, you can enhance your ability to analyze data, extract insights, and develop data-driven solutions.

See salaries and explore the career path for Data Scientist

Database Administrator

Database Administrators ensure the smooth functioning and efficient management of databases, maintaining data integrity and security. This course can help you develop a strong understanding of problem-solving techniques and data structures, which are essential for success in database administration. By learning how to approach and solve coding problems effectively, you can enhance your ability to design, implement, and maintain robust database systems.

See salaries and explore the career path for Database Administrator

Game Developer

Game Developers design, develop, and maintain video games, bringing interactive experiences to life. This course can enhance your problem-solving skills, which are crucial for overcoming technical challenges in game development. By learning how to analyze and solve coding problems effectively, you can improve your ability to create engaging and immersive gaming experiences.

See salaries and explore the career path for Game Developer

Mobile Developer

Mobile Developers create and maintain mobile applications for various platforms, including iOS and Android. This course can help you master fundamental coding interview questions that are commonly asked in mobile development interviews. By understanding these concepts, you can enhance your ability to design, develop, and optimize mobile applications that meet user needs and industry standards.

See salaries and explore the career path for Mobile Developer

Web Developer

Web Developers are responsible for designing, developing, and maintaining websites and web applications. This course can equip you with the necessary problem-solving skills to tackle common challenges in web development, such as optimizing website performance, handling user input, and ensuring cross-browser compatibility. By mastering these techniques, you can enhance your ability to create user-friendly and efficient web applications.

See salaries and explore the career path for Web Developer

Business Analyst

Business Analysts bridge the gap between business needs and technical solutions, helping organizations achieve their goals. This course may be helpful by providing you with problem-solving techniques that can be applied to business analysis. By learning how to approach and solve coding problems effectively, you can enhance your ability to analyze business requirements, identify areas for improvement, and drive data-informed decision-making.

See salaries and explore the career path for Business Analyst

Product Manager

Product Managers are responsible for the development, launch, and success of products. This course may be helpful by providing you with problem-solving techniques that can be applied to product management. By learning how to approach and solve coding problems effectively, you can enhance your ability to define product requirements, prioritize features, and track progress towards product goals.

See salaries and explore the career path for Product Manager

Technical Writer

Technical Writers create and maintain technical documentation, such as user manuals, white papers, and help files. This course may be helpful by enhancing your ability to understand and explain technical concepts. By learning how to approach and solve coding problems effectively, you can improve your ability to write clear, concise, and accurate technical documentation.

See salaries and explore the career path for Technical Writer