1...n-1 means that this array's length can be any possible.
i.e. n = 10, that means that this array has 9 elements.
typical shcools math's formula to discribe infinity

Given a sorted array of distinct integers, but in test case you give not sorted array

JS: Node v12 should be used along with the appropriate assertion tools (Mocha + Chai)

A[1...n-1]

So is it zero-indexed or one-indexed?

why is this under dynamic programming?

The random tests aren't random, they all always expect -1. Even better, they also accept undefined ?!?

I'm the F# and OCaml translator, so any suggestions for those could be tossed my way. :)

That's a good criticism; I was "following along" with the Javascript translation and didn't think to check how the Haskell translation worked.

That being said, I found that having the signature as a list actually made my solution simpler. Although I suppose that's subjective ;)

Try to print() the input and figure out what it should return and how it should behave...

Hello. I tried solving this kata in Python. It passed 7 basic tests and then gives a stderr saying that an 'int' object is not subsciptable. I copied the whole function and tried in Python IDLE (Python 3.4.4). I gave it all the signature inputs specified in the basic tests. It didn't give me any kind of error. What has been going wrong?

Thanks :)

Nice test cases.

The description should say what to do if there is no magic in the array (-1 should be returned).

I think it needs test for zero index, e.g. findMagic([0, 5, 5]) === 0.

I'm not sure about that because the description says array A[1...n-1].
Why the first index in the array is 1?
Does it mean that magic index is always >= 1?
If so, it should be more clear.

Thanks for feedback. Added some random tests.