Misleading example. Example is array of arrays, but the tests are done with array of objects.

Yes, it is explained at the bottom, but still unnecessarily misleading. I think it would better if these were consistent - i.e. the example should show objects, or the tests should test an array of arrays as the argument.

Edit: I should add my comment is for the Javascript variation.

Well done! Everybody has to start somewhere!

GREAT Kata. Love the ones that are very easy to understand what it is asking for, yet challenging to code and logic.

That said, I'm pretty disappointed to find out a 4kyu rated kata allows brute force solutions to pass. On my system, the difference between my solution and another accepted solution for the number 19,999,999 was 38.4 seconds vs 0.11 seconds.

Writing a efficient algorithm for this does feel worthy of 4kyu rating though, and you get more out of it. Thumbs way up.

At first I thought this kata was easier (like 7kyu) but after I tried it, I realized it is indeed 6kyu (albeit on the easy side of 6kyu). I love these easy to understand, but more challenging to actually do type of katas. Katas that require some crazy long explanation to do can sometimes get tedious just to understand what is being asked -_-.

Saw this in the recent comments, now I see what all the hooplah is about, lol.

Please solve this linear before you call it best practice...