ScriptdrillRotate an array
A JavaScript exercise from Scriptdrill. Solve it with a code editor in your browser that runs your function against example and hidden tests, and it is checked the moment you submit.
The task
Return a new array with the items of `arr` rotated `k` steps to the right: each step moves the last item to the front. `k` can be larger than the length (rotating a 3-item array 4 steps is the same as 1 step) and can be negative, which rotates to the left. An empty array returns `[]`. Do not change `arr`.
What this exercise teaches
Rotating by the length changes nothing, so only k modulo the length matters. The double remainder turns a negative k into the equivalent rotation to the right, and two slices build the result without touching the input.
A hint if you get stuck
Reduce `k` to a number of steps between 0 and the length with the remainder operator. In JavaScript `%` keeps the sign of the left side, so use `((k % n) + n) % n`. Then join two slices.
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