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Problem Solving Checklist

  1. Clarifying Questions

    Ask clarifying questions to make sure you understand the scope of the problem so that you'll be solving the right problem. The interviewer may be testing you to see if you know how to gather requirements and communicate.

    Don't rush into coding and risk solving the wrong problem or missing the interviewer's point. This is your chance to shine, to show the interviewer that you can communicate well and get to the heart of problems.

  2. Identify Pattern

    Identify patterns: does this problem look like a search, dynamic programming, graph, or sorting problem? Don't have to tell your interviewer. This step is for yourself.
  3. Examples and Test Cases

    Come up with examples and test cases. This will make the problem concrete and provide test cases with which you will test your solution later on.
  4. Brainstorm Approaches

    Come up with 2-3 approaches and briefly run them by the interviewer but don't write up any code yet. If you need some time to come up with the optimal solution, you can start by outlining what a brute force solution would look like.
  5. Running time and space (Big-Oh for interviews)

    Do basic running time and space complexity estimates for your approaches.
  6. Code

    Code quickly, systematically, and cleanly.
  7. Test

    Test & debug

    Don't forget to double check your work and walk through the solution using one of the test cases you came up with.

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