Algorithms for Coding Interviews in Java

The ultimate guide to coding interviews in Java. Developed by FAANG engineers, tackle 50+ challenge problems, review detailed solutions, and learn strategies to craft optimal solutions.

Intermediate

151 Lessons

15h

Certificate of Completion

The ultimate guide to coding interviews in Java. Developed by FAANG engineers, tackle 50+ challenge problems, review detailed solutions, and learn strategies to craft optimal solutions.

AI-POWERED

Mock Interview

Explanations

AI-POWERED

Mock Interview

Explanations

This course includes

140 Playgrounds

50 Challenges

17 Quizzes

This course includes

140 Playgrounds

50 Challenges

17 Quizzes

Course Overview

Algorithms are one of the most common themes in coding interviews, so having a firm grip on them can be the difference between being hired or not. After this comprehensive course in Java, one of the most popular coding languages, you'll have an in-depth understanding of different algorithm types and be equipped with a simple process for approaching complex analysis. As you progress through the course, you’ll be exposed to the most important algorithms that you're likely to encounter in an interview. You'l...Show More

TAKEAWAY SKILLS

Java

Programming Language

Prepare For Interview

Algorithms

Time Complexity

Course Content

Introduction

Get familiar with foundational concepts, coding challenges, and advanced problem-solving strategies for Java.

Intended Audience

Learning Outcomes

Algorithmic Paradigms

Grasp the fundamentals of brute force, greedy algorithms, divide and conquer, and dynamic programming.

Asymptotic Analysis

Master the steps to asymptotic analysis, comparing algorithm complexities, and solving complexity challenges.

Comparing Algorithms

Example: Measuring Time Complexity of a Single Loop Algorithm

Example: Time Complexity of an Algorithm With Nested Loops

Introduction to Asymptotic Analysis and Big (O)

Other Common Asymptotic Notations and Why Big (O) Trumps Them

Useful Formulae

Common Complexity Scenarios

Challenge: Big (O) of Nested Loop with Addition

Solution: Big (O) of a Nested Loop with Addition

Challenge: Big (O) of Nested Loop with Subtraction

Solution: Big (O) of a Nested Loop with Subtraction

Challenge: Big (O) of Nested Loop with Multiplication

Solution: Big (O) of Nested Loop with Multiplication

Challenge: Nested Loop with Multiplication (Basic)

Solution: Nested Loop with Multiplication (Basic)

Challenge: Nested Loop with Multiplication (Intermediate)

Solution: Nested Loop with Multiplication (Intermediate)

Challenge: Nested Loop with Multiplication (Advanced)

Solution: Nested Loop with Multiplication (Advanced)

Challenge: Nested Loop with Multiplication (Pro)

Solution: Nested Loop with Multiplication (Pro)

Complexity Interview Questions

Sorting and Searching

Discover algorithm techniques for sorting (like Merge Sort and QuickSort) and efficient searching methods.

Selection Sort, Bubble Sort, and Insertion Sort

Merge Sort

Quicksort

Time Complexities of Sorting Algorithms (Overview)

Searching Algorithms

Challenge: Find Two Numbers that Add up to "n"

Solution: Find Two Numbers that Add up to "n"

Challenge: Search in a Rotated Array

Solution: Search in a Rotated Array

Challenge: Group Anagrams

Solution: Group Anagrams

Challenge: Find the Median of Two Sorted Arrays

Solution: Find the Median of Two Sorted Arrays

Challenge: Find Duplicates in Array

Solution: Find Duplicates in Array

Challenge: Search in Sorted Matrix

Solution: Search in Sorted Matrix

Challenge: Count Element Occurrence

Solution: Count Element Occurrence

Challenge: Search Insert Position

Solution: Search Insert Position

Challenge: Sparse Search

Solution: Sparse Search

Challenge: Dutch National Flag Problem

Solution: Dutch National Flag Problem

Quiz on Sorting & Searching

Dynamic Programming

Deepen your knowledge of dynamic programming techniques for solving complex coding problems efficiently.

Greedy Algorithms

20 Lessons

Follow the process of designing and implementing efficient greedy algorithms to solve diverse optimization problems.

Divide and Conquer

23 Lessons

Master the steps to applying divide and conquer for efficient problem-solving in algorithm design.

Graph Algorithms

22 Lessons

Sharpen your skills in implementing and solving diverse graph algorithms efficiently.

Appendix: Auxiliary Source Code

5 Lessons

Unpack the core of auxiliary classes like Stack, Queue, PriorityQueue, HashMap, and ArrayList.

10.

Conclusion

2 Lessons

Master the steps to understand efficient algorithms and enhance your technical interview skills.

Course Author

Trusted by 1.4 million developers working at companies

Anthony Walker

@_webarchitect_

Evan Dunbar

ML Engineer

Carlos Matias La Borde

Software Developer

Souvik Kundu

Front-end Developer

Vinay Krishnaiah

Software Developer

Eric Downs

Musician/Entrepeneur

Kenan Eyvazov

DevOps Engineer

Souvik Kundu

Front-end Developer

Eric Downs

Musician/Entrepeneur

Anthony Walker

@_webarchitect_

Evan Dunbar

ML Engineer

Hands-on Learning Powered by AI

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Instant Code Feedback

Evaluate and debug your code with the click of a button. Get real-time feedback on test cases, including time and space complexity of your solutions.

AI-Powered Mock Interviews

Put your skills to the test in a simulated interview setting. Receive personalized feedback based on your performance. Available in Premium & Premium Plus plans.

Adaptive Learning

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Explain with AI

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AI Code Mentor

AI Code Mentor helps you quickly identify errors in your code, learn from your mistakes, and nudge you in the right direction — just like a 1:1 tutor!

Frequently Asked Questions

How do I prepare for a Java coding interview?

Focus on mastering data structures (arrays, linked lists, stacks, queues, trees, graphs) and algorithms (sorting, searching, dynamic programming). Practice on platforms like Educative. Get comfortable with Java-specific features like collections, generics, and streams. Time management is crucial, so simulate timed coding interviews.

Is Java a good choice for coding interviews?

Yes, Java is a great language for coding interviews. It offers a balance of readability, ease of debugging, and rich built-in libraries for data structures and algorithms. Many top tech companies expect candidates to use languages like Java for coding interviews.

How do I improve my Java coding skills?

Regularly practice coding problems, explore open-source projects, and review Java’s core concepts like OOP, exception handling, and multithreading. Read code written by experienced developers, contribute to Java forums, and stay updated with Java’s latest features.

How do I write fast code in Java?

Write efficient algorithms by understanding time and space complexity. Use appropriate data structures from Java’s collections framework and avoid unnecessary memory allocations. Opt for primitive data types where possible and utilize Java’s profiling tools to identify and optimize bottlenecks.

Why is Java good for algorithms?

Java is widely used for algorithms due to its high-level abstraction and performance balance. Its rich libraries (like java.util) provide efficient implementations of common data structures, making it easy to focus on problem-solving. Additionally, Java’s strict typing helps catch errors early during development.