#Arrays

Chunk Array

Split an array into groups of a fixed size, with whatever is left over in a shorter final group.

By Pratik RaiEasy
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Write chunk(arr, size) splitting the array into subarrays of length size.

The final group holds the remainder and may be shorter. A size of zero or less cannot produce groups — return an empty array.

Examples

Input:

JSfile.javascript
1chunk([1, 2, 3, 4, 5], 2);

Output:

[[1, 2], [3, 4], [5]]

Two full groups and a remainder of one.

Constraints

  • 0 <= arr.length <= 10^5
  • Any integer size

Notes

  • slice past the end of an array simply stops, so the short final group needs no special case.

Goal: Return groups of the requested size, with a short final group when needed.

Source

Frequently asked questions

How do you split an array into chunks?
Loop with a step equal to the chunk size and take a `slice` each iteration. The final slice returns whatever is left, so a short last group needs no special handling.
What should happen with a size of zero?
Nothing sensible can be produced, and an unguarded loop with `i += 0` never advances — it hangs the tab rather than throwing. Guard it and return an empty array.
Does chunking copy the data?
`slice` produces new arrays holding the same element references, so the groups are independent containers but the objects inside them are still shared with the input.
Where is chunking useful?
Paginating a list in memory, laying out a grid row by row, or splitting a large upload or API payload into batches the server will accept.

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