Shuffle array

OSCC · JavaScript, Array, Random, Algorithm · Feb 20, 2021

Randomizes the order of the values of an array, returning a new array.

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

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