As a new user who only joined 2 days ago, I appreciate the explanation. Your toxicity, however, was entirely superfluous. Thanks.

I don't think it's the best solution from programming point of view.

Actually, it is. There's a reason why every IT student has to take math classes. Try to understand Machine Learning without Statistics, or Image Processing without Analysis, or Computer Graphics without Linear Algebra. Without at least some basic maths, you'll be lost as soon as your solution doesn't work, or when you have to implement something non-standard.

colors could be an array instead.

@Chrono79
Is that really necessary? If you can read my comment, you already know the solution it contains. Am I missing something?

This code is very slow for large arrays. You could easily fix this by checking for walk.length === 10 before executing all the filters.

But only when the array has 10 elements, so it's technically still O(1).

Hint: the values of a1 and a2 are not necessarily in the same order.

If $a1 == [1, 1, 1] and $a2 == [1, 2, 3], your code will return true, when it should be false.