How to Use LeetCode Effectively to Prepare for Interviews

Introduction

• Speaker has solved over 1500 LeetCode problems and cleared interviews at Amazon, Google, and Microsoft.
• Aim: To share tips to make the LeetCode journey easier and less painful.

Why LeetCode?

• Necessary for Big Tech company interviews (Amazon, Google, Microsoft).
• Some startups don't require LeetCode practice.

Choosing a Programming Language

• Popular Languages: C++, Java, Python, JavaScript.
• For Beginners: Python—easy to start with and simple syntax.
• Stick with Known Languages: Understand basic syntax, loops, conditionals, functions, I/O operations.
• No major advantage in choosing one language over another for interviews.

Learning Data Structures and Algorithms (DSA)

• Fundamentals: Time and space complexity, basic data structures, and algorithms.
• Big O Notation: Understand and calculate time and space complexity.
• Basic Data Structures: Arrays, strings, binary trees, linked lists, stacks, queues, hashmaps.
• Basic Algorithms: String searching, recursion.
• Resources:
  • YouTube: William Faet's data structure playlist
  • Books: "Data Structures and Algorithms Made Easy" by Narasimha Karumanchi, "Cracking the Coding Interview" by Gayle Laakmann McDowell

Which LeetCode Problems to Solve?

• Beginner Approach: Solve by topic, start with easy problems, gradually move to medium and hard problems.
• Focus on Medium Level: Most interview questions are medium level.
• Curated Lists: NeetCode 75, Top 100 Liked, Top Interview 150 on LeetCode.
• Avoid highly disliked questions to prevent demotivation.

Optimal Problem Solving Strategy

• Number of Problems: Quality over quantity; aim for deep understanding.
• Fun Factor: Keep the practice enjoyable.
• Problem Solving Approach:* Understand the problem statement, start with a brute-force solution, and optimize.
• Analyze Complexity: Time and space complexity for each solution.

Handling Stuck Situations

• Spend 30-60 minutes before seeking hints or solutions.
• Understand solutions fully and try to re-implement them.
• Revisit difficult problems for reinforcement.

Speed and Efficiency

• Learn Patterns: Focus on problem-solving patterns instead of individual questions.
• Practice Under Timed Conditions: Use LeetCode Timer extension, participate in LeetCode contests.

Memorization

• Avoid memorizing solutions; understand underlying principles and patterns.
• Explain thought process during interviews.

Premium LeetCode Subscription

• Not necessary for beginners.
• Free resources available online for problem explanations and visual solutions.

Final Tips and Encouragement

• Practice consistently and keep challenging yourself.
• Resources and example problems are plentiful online.
• More personal stories and experiences are available in the speaker’s other videos.

Conclusion

• Open to questions and suggestions for future video topics.
• Wishes viewers best of luck.