@OlegSonin: you should read this whole thing. It was created specifically for people like you who do not enough masterize cw' environment yet. Lots of useful info for you in there.

cheers.

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

You can make two strings of 2 consecutive strings taken in the array there:

"Hellolongest" length 12
"longestworld" length 12

"Hellolongest" is the first one, they have the same length.

longestConsec(["Hello", "longest", "world"], 2) // The result for this test should be "Hellolongest", your function returns "longestworld"

And how exactly is it broken?