How to Start Leetcode (as a beginner)

Summary

In this video, the speaker shares insights from solving over 1500 coding problems and clearing interviews at tech giants like Amazon, Google, and Microsoft. They guide viewers on how to start with LeetCode, choose a programming language, and the importance of understanding data structures and algorithms. They recommend starting with easy problems, focusing on medium difficulty for interviews, and learning from each problem rather than just the quantity. Tips on approaching new problems, using resources like YouTube and books, and practicing in a timed environment are also provided.

Takeaways

• 😀 You can get a software development job without coding on LeetCode, but it's beneficial for interviews at big tech companies like Amazon, Google, and Microsoft.
• 🔍 There's no one 'right' programming language for coding interviews; popular languages like C++, Java, Python, or JavaScript are all acceptable.
• 👶 For beginners in coding, Python is recommended due to its simplicity and ease of learning.
• 🌟 Understanding basic programming concepts like loops, conditionals, functions, and basic input/output operations is crucial, regardless of the language you choose.
• 📚 To learn data structures and algorithms, resources like William Fiset's YouTube channel and books like 'Data Structures and Algorithms Made Easy' are helpful.
• 🎯 Start with problems by topic on LeetCode to deepen your understanding and learn when to use specific data structures or algorithms.
• 🚀 Focus on medium-level problems, as these are typically what you'll encounter in interviews, rather than getting stuck on hard problems early on.
• 🤔 When starting, aim to solve 300 to 400 problems to build a strong foundation, focusing on understanding rather than just the quantity.
• 🕒 Spend at least 30 to 60 minutes on a problem before looking at solutions; understand and implement the solution to reinforce learning.
• 📈 Learn to recognize patterns in problems on LeetCode, as many follow similar approaches, which can speed up your problem-solving.
• 💡 Memorizing solutions is not effective; understanding the logic and being able to explain your thought process is key for interviews.

Q & A

Why is practicing on LeetCode recommended for job interviews at big tech companies?

Practicing on LeetCode is recommended because it's an effective platform to prepare for technical interviews at big tech companies like Amazon, Google, and Microsoft, where coding challenges are a common part of the hiring process.

Can you get a software development job without doing LeetCode?

Yes, it's possible to get a software development job without doing LeetCode, especially at startups that may not focus on such coding challenges. However, for roles at big tech companies, LeetCode practice is beneficial.

What programming language should one use for LeetCode and interviews?

There is no single 'right' language; any popular language like C++, Java, Python, or JavaScript is suitable. For beginners, Python is recommended due to its simplicity and ease of learning. It's best to stick with a language you're comfortable with and understand its basic syntax and concepts.

Does the choice of programming language matter in big tech interviews?

No, as long as it's a well-known language, the choice doesn't matter much because a programming language is just a tool, and problems can be solved using multiple languages.

What should a beginner know before starting to solve LeetCode problems?

A beginner should have a basic understanding of computer science fundamentals, including time and space complexity, and be familiar with fundamental data structures and algorithms. Concepts like loops, conditionals, functions, and basic input/output operations are essential.

How can one learn data structures and algorithms effectively?

One can learn through various online resources, such as YouTube channels like William Fiset, which provides visual explanations, or books like 'Data Structures and Algorithms Made Easy' by Nariman Gulam and 'Cracking the Coding Interview' by Gayle Laakmann McDowell.

How should a beginner approach solving LeetCode problems?

Beginners should start by solving problems by topic to gain a deeper understanding. Start with easy problems and gradually move to more challenging ones. Focus on medium-level problems as they are most commonly encountered in interviews.

How many problems should one aim to solve on LeetCode?

The number of problems varies based on the individual's level. For beginners, solving 300 to 400 problems is generally sufficient. The focus should be on understanding rather than just increasing the count.

How does one effectively approach a new LeetCode problem?

Take time to understand the problem statement, expected input/output, and start with a brute force solution. Then, work on optimizing it by reducing time and space complexity. Plan your approach before coding and develop the habit of analyzing the complexity of your solutions.

When should one look at the solution if stuck on a LeetCode problem?

If you're stuck, give at least 30 to 60 minutes of focused effort. If still stuck, look at hints or solutions. It's important to understand and try to implement the solution yourself, not just move on.

How can one practice solving problems like they are in an interview?

Practicing in a timed environment is crucial. Using tools like the LeetCode timer or participating in LeetCode contests can simulate the interview experience. It's about gaining experience solving problems within a time limit.

Is a LeetCode premium subscription necessary for beginners?

Not necessarily. While premium offers access to exclusive problems and visual solutions, these can often be found for free online. A premium subscription may be more beneficial for those looking for additional resources or a more structured learning path.