Algie
TDD-based algorithm training exercices

Motivations behind the project

Teach someone algorithmic I needed to teach a student algorithm and best practices, and I found that a simple Github project is the perfect tool. He/she can ask for a Pull Request per function, that teacher can then review and comment. That's a classic, but efficient workflow for teaching.

Daily training for everybody I tried to create a very easy onboarding for junior developers. No subscription, zero tool required. If you know how to open a web page in a browser and write some standard JS function, that's enough. However, experienced developers should find it interesting enough : exercices are sorted into difficulty order, so just skip the first exercices if it's too easy, and code where it begins to be interesting.

Wild examples... Most of the time, exercices are extracted from encountered situations on real web project. Sometimes, spec are left a litlle bit ambiguous to encourage the student to justify and specify weird cases by himself/herself, as it happen in the wild.

...but standard problems There is nothing related to JavaScript traps or tricks, all problems mostly deal with standard types you will find in most langages (String, Hash, Array, etc), that can be solved by classic primitives (map, reduce, filter, etc). Thus, you can reuse the specs to train in other langages.

How to solve algorithmic problems

• Google around if the problem has already been solved somewhere
• If not, break the problem into a suit of smaller problems
• Google around each smaller problem
• Still not found ? Use console.log a lot
• Still not found ? Clearly illustrate your problem on Stackoverflow
• Find and use other channels than Stackoverflow
• Rely a lot on external librairies. In JavaScript, Lodash is very efficient to solve algorithms problems
• Try to name your variable so that a non-coder could understand what it means
• Try to return always the same type to avoid side-effects when chaining calls
• Try a more functional approach, which is more robust and efficient
• Do not to be afraid of huge chunk of code of API response. This is how it happens in the real world, and "huge" doesn't necesseraly mean "more difficult"
• Commit very, very frequently. It helps to see where things started to go wrong
• Try to find at least 2 examples (specifications) of the "happy path"
• Try to check if a specification is simply wrong
• Try to think about which specification could be missing
• If a specification is missing, try to write a test first
• Try to think about side-effects
• Try to use a debugger (Chrome has a good one)
• Try to train every day
• Try not to do a too difficult task when training, because this won't help
• Try not to do a too easy task when training, because this also won't help
• Try to find a solution as quick as possible, even if you feel it as "very dirty"
• Try to improve the solution once you found it
• Try to redo exercices that was already solved a few weeks ago