Data Structures & Algorithms in Java + 130 Leetcode Problems

Pratik Singhal

Picture this: You're sitting in the hot seat of a coding interview, faced with a challenging DSA problem. How do you tackle it with confidence and perfection? That's where my course comes in.

In this course, I am taking you straight to the heart of the action – the top 130 Leetcode problems. Why these specific ones? Because they're the ones tech companies love to throw your way. By mastering these, you'll be ready to ace any coding interview that comes your way.

If you’re wondering why Leetcode?

Picture this: You're sitting in the hot seat of a coding interview, faced with a challenging DSA problem. How do you tackle it with confidence and perfection? That's where my course comes in.

If you’re wondering why Leetcode?

Leetcode is the most popular platform that offers a vast array of coding challenges, frequently used by tech companies in their hiring processes.

Here's why this course is will help you:

We're not simply tossing problems your way and crossing our fingers. Nope, not here.

We will together dive deep into each problem for invaluable insights into underlying concepts and problem-solving techniques, helping you to truly understand and conquer every challenge.

You’ll learn systematic approaches to problem-solving. We’ll help you break them into manageable tasks and craft efficient algorithms, so you can confidently tackle any challenge that comes your way.

One standout feature of this course is the live code implementation. You'll see each problem solved in real-time, giving you a firsthand look at the coding process.

Enhance your coding abilities through practical, hands-on learning, ensuring you're well-prepared for real-world scenarios.

Discover efficient coding practices, optimization techniques, and common pitfalls to avoid, equipping you with the skills to write clean, efficient code.

Follow along step-by-step as we dissect each problem in detail, guiding you through the thought process and live code implementation.

You get to access code sample files accompanying the video lectures, serving as valuable references and guides to support your learning journey and help you implement solutions effectively.

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What's inside

Learning objectives

Top 130 coding interview problems on leetcode
Data structure & algorithms theory with implementation
Leetcode practice problems on dynamic programming, greedy algorithms in java

Leetcode practice problems on graphs, trees, backtracking in java
Leetcode practice problems on arrays, sliding window, two pointer, ad hoc problems in java

Top 130 coding interview problems on leetcode
Data structure & algorithms theory with implementation
Leetcode practice problems on dynamic programming, greedy algorithms in java
Leetcode practice problems on graphs, trees, backtracking in java
Leetcode practice problems on arrays, sliding window, two pointer, ad hoc problems in java

Syllabus

Course Introduction

How to get started with Leetcode ?

In this section we will learn how to calculate time and space complexity for any algorithm from scratch. By the end of this section you will become proficient in time and space complexity calculation

Introduction to Time & Space Complexity

What is Big O Notation ?

Checking If Big O Notation Is Acceptable

Calculating Time Complexity Example 1

Calculating Time Complexity Example 2

Myth About Time Complexity 1

Calculating Space Complexity

Calculating Time Complexity Of Recursive Cases

Space Complexity Calculation Simple Case

Recursive Time Complexity Example 2

Recursive Space Complexity Example 2

Time Complexity Live Demonstration

In this section you will solve problems based on arrays and its associated techniques like Two Pointer Method, Sliding Window Algorithm etc.

What are arrays and why are they so fast!

Drawbacks of using Arrays

How do resizable arrays work ?

Important Array Methods In Java Part 1

Leetcode #53 - Maximum Sum Subarray - Java

Leetcode #121 - Best Time To Buy And Sell A Stock - Java

Leetcode #152 - Maximum Product Subarray - Java

Leetcode #238 - Product Of Array Except Self - Java

Leetcode #189 - Rotate Array - Java

Leetcode #485 - Max Consecutive Ones

Leetcode #36 - Valid Sudoku - Java

Leetcode #973 - K Closest Points To Origin - Java

Practice Problem 4 - Encode and Decode Strings

Sliding Window Method + Sliding Window Method Practice Problems

What is Sliding Window method ? - Part 1

What is Sliding Window Method ? - Part 2

How to implement Sliding Window Method Problems Quickly ?

Practice Problem 1 - Longest Substring Without Repeating Characters

Practice Problem 2 - Longest Repeating Character Replacement

Practice Problem 3 - Sliding Window Maximum - Java

Two Pointer Method

Leetcode #11 - Container With Most Water - Java

Leetcode #42 - Trapping Rain Water - Java

Leetcode #167 - Two Sum II - Input Array Is Sorted - Java

Valid Palindrome - Java

Leetcode Practice Problems Based On Intervals

Leetcode #57 - Insert Interval

Leetcode #35 - Search Insert Position - Java

Practice Problem 3 - Merge Intervals

Leetcode #252 - Meeting Rooms - Java

Leetcode #435 - Non Overlapping Intervals

Leetcode Practice Problems Based On Math & Geometry

Leetcode #73 - Set Matrix Zero - Java

Leetcode #48 - Rotate Image

Leetcode #54 - Spiral Matrix - Java

Pow (X, N)

Sorting Theory + Sorting Practice Problems

Leetcode #169 - Majority Element - Java

Leetcode #75 - Sort Colors - Java

Leetcode #283 - Move Zeroes - Java

In this section we will go through the practice problems based on recursion and backtracking

What is backtracking and how it is implemented ?

Backtracking Example 1 With Detailed Implementation

Leetcode #39 -Combination Sum - Java

Leetcode #78 - Subsets - Java

Leetcode #51 - N Queens - Java

Leetcode #46 - Permutations - Java

Leetcode #90 - Subsets II - Java

Leetcode #40 - Combinations Sum II

Leetcode #17 - Letter Combinations Of A Phone Number

Leetcode #79 - Word Search

Leetcode #212 - Word Search II

In this section we cover Binary Search Leetcode Problems

Introduction To Binary Search

Binary Search Implementation

Binary Search Complexity

Leetcode #34 - Find First And Last Position Of Element In Sorted Array - Java

Leetcode #33 -Search In A Rotated Sorted Array - Java

Leetcode #875 - Koko Eating Bananas - Java

Leetcode #1552 -Magnetic Force Between Two Balls - Java

Leetcode #153 - Find Minimum In A Rotated Sorted Array - Java

In this section we will learn the different techniques required to solve Binary Search Tree Problems

Introduction To Binary Search Trees

Height Balanced BST

BST Insertion

Inorder Successor And Predecessor

BST Deletion

Leetcode #230 - Kth Smallest Element In BST - Java

Leetcode #98 - Validate Binary Search Tree - Java

Leetcode #235 - Lowest Common Ancestor Of A Binary Search Tree - Java

Binary Trees Theory + Leetcode Practice Problems

Introduction to Binary Trees

Terms Related To Trees

Level Order Traversal

Tree Traversal Algorithms

Leetcode #94 - Binary Tree InOrder Traversal - Java

Leetcode #101 - Symmetric Tree - Java

Leetcode #104 - Maximum Depth Of A Binary Tree - Java

Leetcode #226 - Invert Binary Tree - Java

Leetcode #543 - Diameter Of A Binary Tree - Java

Leetcode #102 - Binary Tree Level Order Traversal - Java

Leetcode #112 - Path Sum - Java

Leetcode #113 - Path Sum II - Java

Leetcode #993 - Cousins in Binary Tree - Java

Good to know

Know what's good

, what to watch for

, and possible dealbreakers

Develops expertise of top 130 Leetcode problems, essential for passing coding interview challenges

Strengthens foundational coding skills and deepens understanding of data structures and algorithms

Covers a variety of problem-solving techniques, including dynamic programming, greedy algorithms, and backtracking

Provides hands-on practice and prepares learners to tackle real-world coding challenges

Led by Pratik Singhal, an expert in coding interviews with a proven track record

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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 Data Structures & Algorithms in Java + 130 Leetcode Problems with these activities:

Review Basic Programming Concepts

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Review basic programming concepts to refresh your knowledge and ensure you have a solid foundation for the course.

Browse courses on Programming Fundamentals

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Go over your notes or textbooks from previous programming courses.
Practice writing simple code snippets to implement basic programming concepts such as variables, data types, and control flow.
Solve easy LeetCode problems to apply your refreshed programming skills.

Organize Your Course Materials

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Organize your course materials such as notes, assignments, quizzes, and exams to improve your ability to find and review them later.

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Create folders or use a digital tool to organize your course materials.
Label and group related materials together.
Regularly update and review your organized materials.

Read a Book on Data Structures and Algorithms

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Review a book on data structures and algorithms to strengthen your foundational knowledge and prepare for coding interviews.

View Introduction to Algorithms, fourth edition on Amazon

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Choose a book on data structures and algorithms that aligns with your skill level.
Read the book thoroughly and take notes on important concepts.
Practice implementing data structures and algorithms in the programming language of your choice.
Solve LeetCode problems using the concepts you learned from the book.
Discuss the book and your learnings with peers or instructors.

Five other activities

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Join a Study Group for LeetCode Problems

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Join a study group to collaborate with other students, discuss different approaches to LeetCode problems, and learn from each other.

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Find a study group or create your own with classmates.
Choose LeetCode problems to work on together.
Meet regularly to discuss your solutions and learn from each other.
Share resources and tips related to LeetCode problems.
Provide peer support and encouragement to each other.

Watch Video Lectures on LeetCode Problems

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Watch video lectures from the course to gain insights into different LeetCode problems and solution approaches.

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Choose a LeetCode problem from the course syllabus.
Watch the corresponding video lecture for that problem.
Take notes on the problem-solving approach and implementation details.
Pause the video and try to solve the problem on your own.
Resume the video to check your solution and learn from the instructor's approach. (recommended)

Practice LeetCode Problems

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Practice solving LeetCode problems to improve your problem-solving skills and prepare for coding interviews.

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Pick a LeetCode problem from the course syllabus.
Read the problem statement carefully and understand the requirements.
Break down the problem into smaller subproblems.
Implement your solution in the programming language of your choice. (e.g. Java)
Test your solution against the given test cases.

Create a LeetCode Problem Collection

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Create a collection of LeetCode problems that you have solved or found particularly challenging to reinforce your learning and prepare for coding interviews.

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Identify LeetCode problems that you found interesting or challenging.
Organize the problems into categories or topics.
Create a document or use a tool to store the problem statements, your solutions, and any additional notes.
Review your collection regularly to refresh your knowledge and identify areas for improvement.

Write a Summary of a LeetCode Problem

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Summarize a LeetCode problem to solidify your understanding and improve your communication skills.

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Pick a LeetCode problem from the course syllabus.
Solve the problem on your own or with the help of course materials.
Write a summary that includes the problem statement, your solution approach, and the time and space complexity of your solution.
Proofread your summary for clarity and accuracy.
Share your summary with a peer or instructor for feedback.

Career center

Learners who complete Data Structures & Algorithms in Java + 130 Leetcode Problems will develop knowledge and skills that may be useful to these careers: