Array union

JavaScript, Array · Oct 22, 2020

Returns every element that exists in any of the two arrays at least once.

Create a Set with all values of a and b and convert it to an array.

const union = (a, b) => Array.from(new Set([...a, ...b]));

union([1, 2, 3], [4, 3, 2]); // [1, 2, 3, 4]

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