30-seconds-of-code/snippets/cartesian-product.md

title, type, tags, cover, dateModified

title	type	tags	cover	dateModified
Cartesian product	snippet	math	sail-away	2020-12-29T12:31:43+02:00

Calculates the cartesian product of two arrays.

• Use Array.prototype.reduce(), Array.prototype.map() and the spread operator (...) to generate all possible element pairs from the two arrays.

const cartesianProduct = (a, b) =>
  a.reduce((p, x) => [...p, ...b.map(y => [x, y])], []);

cartesianProduct(['x', 'y'], [1, 2]);
// [['x', 1], ['x', 2], ['y', 1], ['y', 2]]