I like this reduce solution more than mine. Nice work! +1

Why do some of the test cases have fewer zeroes in the output than in the input?

Not what the kata asks. If it ask for the first one, that's what your function should return.

Why are you sorting? In javascript sort modifies the array in place, and you shouldn't sort at all.

Your task is to return the first longest string consisting of k consecutive strings taken in the array.

So in case of a tie, you should return the first one.

I think the random tests are broken in terms of a tie. I sorted by length and then alphabetically and it doesn't work.. Passing 190/200 random tests on average