Longest Substring Without Repeating Characters (LeetCode 3) | 🔥 DSA Java Placement Course

In this video, we will solve one of the most popular string problems asked in coding interviews — Longest Substring Without Repeating Characters (LeetCode 3).

This question is a classic example of how to use the Sliding Window Technique and HashMap efficiently in Java.

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You’ll learn:
✔ What the problem is asking
✔ Step-by-step explanation of the logic
✔ How the sliding window expands and shrinks
✔ Updating window boundaries using HashMap
✔ How to write the clean and optimized Java solution
✔ Time and space complexity
✔ Tips for cracking similar string and window problems in technical interviews

Whether you’re preparing for placements, internships, coding interviews, or learning DSA in Java, this video will help you master the concept clearly.

⭐ Timestamps
00:00 – Introduction
00:12 – Longest Substring Problem Explanation
01:52 – Longest Substring Problem Solved using Sliding Window Concept
14:27 – Longest Substring Problem Solved using HashMap

📘 Topics Covered in This Video
✔ Longest Substring Without Repeating Characters
✔ LeetCode 3 Java Solution
✔ Sliding Window Algorithm
✔ Variable Size Sliding Window
✔ HashMap Based Approach
✔ Java String Interview Questions
✔ DSA Java Placement Course
✔ Frequently Asked Interview Problems
✔ Coding Interview Preparation
✔ Most Asked String Problems

🔥 This video is perfect for:
✔ Students preparing for placements
✔ Candidates appearing for technical interviews
✔ Beginners learning DSA in Java
✔ Anyone solving LeetCode problems
✔ Those who want a clear explanation of sliding window

🧑‍💻 HashTags (SEO Friendly)
#dsa #java #leetcode #slidingwindow #codinginterview #datastructures #placements #stringproblems #leetcode3 #javaprogramming