This is a note of the various things related to competitive programming / doing interviews that I've gathered so far.
- Blind75 - Curated List of Top 75 LeetCode Questions to Save Your Time | Tech Industry - Blind
- Hacker Rank skill certification / verification
- Build a SaaS product with Next.js, Supabase and Stripe | egghead.io
- Top Interview 150 - Stdy Plan - LeetCode
- Blind75 - Curated List of Top 75 LeetCode Questions to Save Your Time | Tech Industry - Blind
- TopSWE
- fishercoder1534/Leetcode: Solutions to LeetCode problems; updated daily. Subscribe to my YouTube channel for more.
- Graph problems
- Solve Algorithms | HackerRank
- NeetCode - Practice
- System design - Primer · CatalanCabbage/notes
- systemdesign42/system-design: A resource to help you pass system design interview and become good at work 👇
- ByteByteGoHq/system-design-101: Explain complex systems using visuals and simple terms. Help you prepare for system design interviews.
- System Design in a Hurry
- More resources: System design interview guide for Software Engineers | Tech Interview Handbook
For prep i used 3 paid resources.
- Coding ninjas (Started here, and i would still start here, considering the 24*7 doubt support )
- Algoexpert ( Good question set)
- LC Premium (Used for assessments)
See also buildyourownx GitHub profile which is great.
A good twitter thread that deeply resonates with me: Akshaya Sivaraman on Twitter: "How did I go from a busily scheduled life to one with substantial unstructured time?
- Initial capacity and load factor affect the performance of hash table / map.
- It is open: in the case of a "hash collision", a single bucket stores multiple entries.
- Iterators returned by "collection view methods" are fail-fast: i.e., they throw
ConcurrentModificationExceptionif they detect a concurrent modification of the underlying hashtable. This is not fool-proof / guaranteed. So, implementations should not depend on the same. - Hashtable is synchronized. HashMap is not. For thread safe usage, a ConcurrentHashMap is recommended.
- JavaDoc
- Hash table cheatsheet for coding interviews | Tech Interview Handbook
- What are hashtables and hashmaps and their typical use cases?
- Listen - Listen carefully to the problem. Every detail is necessary to solve that problem.
- Example - Come up with a good example. Make examples larger and avoid special cases.
- Come up with a brute-force algorithm - It's better to start off with a slow and terrible algorithm than to start of with nothing at all. Don't code the brute-force algorithm. Just state the brute-force algorithm and it's runtime and then go into optimizing it.
- Optimize
- Walk through your algorithm - Don't code prematurely. Take a step back and verify that the algorithm is correct.
- Start coding - For whiteboard: write the line straight, use space wisely; Whiteboard or computer: coding style matters, consistent coding style, naming is important for good style (ask the interviewer if you could abbreviate them the next time), MODULARIZE
- Start testing - analyse, double check things that look weird/risky, small test first, special cases next and if time permits large test cases. Remember: Think as you test. Don't go through the code like a bot. Test your code and not the algorithm!. When you find a bug, don't panic! Give some thought about fixing the bug.
- B.U.D - Bottleneck, Unnecessary, Duplicates - walk through the brute force (to identity bottlenecks, unnecessary and duplicated code)
- Space-time tradeoffs - you can almost always save some time by trading off some space. Think about Hash tables.
- Do it yourself - use a large generic example and try to solve it yourself. You'll identify some nice ways to optimize when solving the problem for a large test case.
- 18/Sep/2024 - Continue working on the optimal solution for the Two sum problem.
- 17/Sep/2024 - Worked on the Two sum problem. Completed the brute-force solution. Was working on optimizing the solution and was reading up on HashMap / HashTable a bit.