Comp Sci Fundamentals
A collection of solutions to common computer science challenges found online, in books, online, or elsewhere.
My intention to is follow a process for methodically walking through each challenge and record the process the same way I would if I were whiteboarding it. Many challenges will include initially sub-optimal solutions and will be built upon with (hopefully) more performant and elegant code as I learn.
Solutions will be implemented in multiple languages, beginning with Ruby, Javascript, and C#.
Process
I will be roughly following the process for walking through a process introduced by Gayle Laakmann McDowell in Cracking the Coding Interview. In summary, the process looks like this:
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Listen
Pay very close attention to any information in the problem description.
In this case, I'll simply be restating the problem with emphasis on any pieces of information I believe will be important to solving the problem.
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Example
Pretty strait-forward. Before tackling the problem I'll provide (or use a provided) example input and expected output. Examples should be big enough and main-case enough to test the validity of any solution.
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Brute Force
Get a brute force solution as soon as possible.
Outline a solution in English or pseudo-code, we won't worry about efficiency at this point.
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Optimize
Walk through the brute force solution and look for ways to improve its efficiency. How does the current performance compare to the best conceivable runtime? Are there potential tradeoffs between time and space?
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Walk Through
Now that you have an optimal solution, walk through your approach in detail.
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Implement
The first five steps will only be walked through once, however this and the next step will be done separately for each language. I'll be writing the code in the markdown, without aid of an IDE in order to simulate a whiteboard. Expect typos/errors, but my goal is to write code that compiles as-is.
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Test
Step through the algorithm with the example, fix any errors that are found.
Collections
License
MIT License
Copyright (c) 2017 Josh Saint Jacque
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