How many days to master LeetCode?

Mastering LeetCode depends on various factors such as your current skill level, your understanding of algorithms and data structures, the time you can dedicate daily, and the goals you're trying to achieve. Mastery is subjective and can mean different things, but generally, it refers to becoming proficient enough to solve LeetCode Medium and Hard problems consistently and efficiently.

Here’s a breakdown of how long it may take to "master" LeetCode for different levels of experience:

1. Factors That Influence How Long It Takes

a. Experience Level

• Beginners: Those with little to no experience in coding or problem-solving.
• Intermediate: Those familiar with basic algorithms and data structures but lacking speed or the ability to solve complex problems efficiently.
• Advanced: Experienced coders who are comfortable with most algorithms and data structures but may need to refine skills for highly challenging problems.

b. Time Commitment

• Daily Practice: If you can dedicate 2-4 hours per day to solving LeetCode problems, you'll progress faster than if you're only able to practice occasionally.
• Consistency: Regular practice is key to mastery. Solving problems daily and reviewing solutions will help reinforce concepts.

c. Goal

• Job Preparation: If your goal is to prepare for interviews at top tech companies, your mastery level will need to be high, especially for Medium and Hard problems.
• Improving General Coding Skills: If you're aiming to improve your overall coding abilities, focusing on Easy and Medium problems might suffice.

2. Estimating the Time Required

a. Beginners (6 to 12 Months)

For beginners who are starting from scratch, it can take 6 to 12 months to master LeetCode. Here’s why:

• Learning Algorithms and Data Structures: You'll need to spend time learning core concepts such as arrays, strings, recursion, linked lists, binary trees, and sorting algorithms. This can take 2-3 months to grasp the basics.
• Solving Easy Problems: After learning the basics, solving Easy problems will help you build confidence. You should aim to solve at least 2-3 problems per day, which can take 2-3 months.
• Moving to Medium Problems: Once comfortable with the basics, you can move on to Medium problems. Solving 4-5 Medium problems per day for 3-4 months will help you develop problem-solving strategies for more complex situations.
• Tackling Hard Problems: Finally, you’ll start working on Hard problems. This stage requires a deeper understanding of algorithms, dynamic programming, and optimization techniques. This final stage can take another 3 months of consistent effort.

Total Time for Beginners: 6 to 12 months of consistent practice, focusing on solving at least 3-5 problems daily.

b. Intermediate (3 to 6 Months)

For someone with some coding background but lacking speed and efficiency, it typically takes around 3 to 6 months to master LeetCode:

• Refreshing Core Concepts: Spend 1 month revisiting algorithms like DFS, BFS, recursion, dynamic programming, and common data structures (trees, graphs, heaps).
• Focusing on Medium Problems: Dedicate 2-3 months solving Medium problems. Try to solve 4-6 problems per day and review multiple solutions to understand different approaches.
• Transitioning to Hard Problems: For the last 2-3 months, work on Hard problems. Solving 2-3 Hard problems per day while reviewing optimizations will help you master more advanced topics.

Total Time for Intermediate Programmers: 3 to 6 months, focusing on solving 4-6 problems daily, mostly Medium and Hard difficulty.

c. Advanced (1 to 3 Months)

If you're already experienced with algorithms and data structures, and you want to sharpen your skills for tough coding interviews, it can take around 1 to 3 months to master LeetCode:

• Target Hard Problems: Start directly with Hard problems or complex Medium problems that are commonly asked in FAANG interviews. Solving 4-6 Hard problems per day will keep your skills sharp.
• Mock Interviews: Spend time simulating real interview environments, either through mock interviews or timed practice sessions. This helps you get used to the time pressure and build confidence for interviews.
• Review and Optimize: Always review your solutions and focus on optimizing time and space complexity. Look at different approaches to solve the same problem.

Total Time for Advanced Programmers: 1 to 3 months with a focus on solving 5-7 Hard problems daily and performing mock interviews.

3. Suggested Daily Practice Plan

Here’s a sample plan for consistent progress:

• Day 1 to Day 30 (1 Month):

  • Beginners: Learn and review data structures like arrays, strings, linked lists, and basic algorithms like sorting.
  • Intermediate/Advanced: Refresh important algorithms like recursion, DFS, BFS, dynamic programming.

• Day 31 to Day 60 (1-2 Months):

  • Beginners: Solve 2-3 Easy problems daily.
  • Intermediate/Advanced: Work on solving 4-5 Medium problems daily.

• Day 61 to Day 120 (2-4 Months):

  • Beginners: Transition to Medium problems (4-5 daily).
  • Intermediate/Advanced: Focus on solving Hard problems (2-4 daily).

• Beyond Day 120:

  • Beginners: Start working on Hard problems to challenge yourself.
  • Intermediate/Advanced: Keep solving Hard problems and participating in mock interviews.

4. Resources to Help You Master LeetCode

• LeetCode: Use LeetCode’s problem categories and difficulty filters to structure your learning. You can also participate in LeetCode contests to test your skills under pressure.

• Courses:

  • Grokking the Coding Interview (Excellent for learning common coding patterns).
  • Grokking Data Structures & Algorithms for Coding Interviews.

• Books:

  • Cracking the Coding Interview by Gayle Laakmann McDowell.
  • Elements of Programming Interviews by Adnan Aziz.

• Mock Interviews:

  • Platforms like Pramp or DesignGurus.io for simulating real coding interview environments.

Conclusion

The time it takes to master LeetCode can range from 1 to 12 months, depending on your starting point, goals, and the amount of time you can dedicate daily. For a complete beginner, it may take up to a year to fully master the platform, while intermediate and advanced programmers may need just a few months of focused practice.

The key to mastering LeetCode is consistent practice, learning from mistakes, and gradually increasing the difficulty level of the problems you solve. With dedication, anyone can significantly improve their problem-solving skills and perform well in coding interviews.