# N random elements in array

Gets `n`

random elements at unique keys from an array up to the size of the array.

- Shuffle the array using the Fisher-Yates algorithm.
- Use
`Array.prototype.slice()`

to get the first`n`

elements. - Omit the second argument,
`n`

, to get only one element at random from the array.

const sampleSize = ([...arr], n = 1) => { let m = arr.length; while (m) { const i = Math.floor(Math.random() * m--); [arr[m], arr[i]] = [arr[i], arr[m]]; } return arr.slice(0, n); }; sampleSize([1, 2, 3], 2); // [3, 1] sampleSize([1, 2, 3], 4); // [2, 3, 1]