30-seconds-of-code/javascript/snippets/powerset.md

title, type, tags, cover, dateModified

title	type	tags	cover	dateModified
Powerset	snippet	math algorithm	new-plant	2021-09-27T15:27:07+02:00

Returns the powerset of a given array of numbers.

• Use Array.prototype.reduce() combined with Array.prototype.map() to iterate over elements and combine into an array containing all combinations.

const powerset = arr =>
  arr.reduce((a, v) => a.concat(a.map(r => r.concat(v))), [[]]);

powerset([1, 2]); // [[], [1], [2], [1, 2]]