Applying this solution


Just a curiosity. How does this problem and solution apply to work that we might do?

It is a fantastic problem and solution. As I am relatively new to doing the kinds of algorithms, for this problem specifically, I am having a really hard time imagining coming up with this solution and this proof on the spot within a 30 minute interview.

I know it now, but if I didn’t see this exact problem set on this platform, what would be the logical steps I would take to come to this conclusion within a short amount of time?

Thank you,


Course: Grokking Coding Interview Patterns in JavaScript - Learn Interactively
Lesson: Solution: Find The Duplicate Number

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Hello @Jeff_Huckabay,

Thank you for reaching out to us. I’m glad you’re curious about how the discussed problem and solution can be useful in real-world scenarios. Your thoughts on this are really valuable, and I appreciate your feedback.

Understanding and applying Floyd’s Cycle Detection Algorithm, or any algorithm, in real life is like figuring out patterns and structures in a problem you want to solve. This duplication problem often arises in real-world scenarios, especially when dealing with data accuracy and validation tasks. Especially when we have datasets expected to have distinct values within a certain range, we have to quickly identify any missing or duplicate values, which can help validate the data’s integrity and accuracy.

Let me also try to explain the steps you could take to solve similar problems quickly:

  1. First, understand the problem statement and identify its constraints and requirements.

  2. Think about similar problems you have encountered before. Note what is common or different in this particular problem.

  3. Analyze the problem statement and the input data to see if any patterns (series, cycles, etc.) are present and could be significant. If cycles are involved, think about the problem involving lists or any data structures where duplicates are allowed.

  4. Use problem-solving tricks by breaking down the problem into smaller sub-problems. Think about different ways to solve each part of the problem.

  5. Think of the solutions you already know and see if they fit on this problem. In the case of finding duplicates, Floyd’s Cycle Detection algorithm might come to mind if there’s a possibility of cycles in the input data.

  6. Practice and refine by re-iterating through potential solutions in your mind. Drop the solutions that seem to be impractical or inefficient. Keep tweaking the solutions coming into your mind if they don’t fit the problem.

  7. Consider the time and space complexity of your proposed solutions in a time-constrained interview. Choose a solution that works well and doesn’t require extensive time to explain or implement in the interview.

  8. Practice more to have exposure to a variety of problems and solutions. The more you practice with different problems, the better you get and apply algorithms quickly to solve a problem. As you practice more problems, you’ll have a collection of tricks/techniques that can be applied to a problem in different scenarios.

Remember that problem-solving skills, especially in technical interviews, improve with practice and experience. Plus, it’s not just about finding the right answer quickly but about showing how you think about the problem.

I hope this explanation helps you in coming up with logical steps within the defined timeframe and help complete your coding interviews. Please feel free to share any more valuable feedbacks and suggestions, we’d be happy to help!

Happy learning!

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