diff --git a/snippets/superSet.md b/snippets/superSet.md new file mode 100644 index 000000000..38cc17ccd --- /dev/null +++ b/snippets/superSet.md @@ -0,0 +1,21 @@ +--- +title: superSet +tags: array,intermediate +--- + +Checks if the first iterable is a superset of the second one. + +- Use the `new Set()` constructor to create a new `Set` object from each iterable. +- Use `Array.prototype.every()` and `Set.prototype.has()` to check that each value in the second iterable is contained in the first one. + +```js +const superSet = (a, b) => { + const sA = new Set(a), sB = new Set(b); + return [...sB].every(v => sA.has(v)); +}; +``` + +```js +superSet(new Set([1, 2, 3, 4]), new Set([1, 2])); // true +superSet(new Set([1, 2, 3, 4]), new Set([1, 5])); // false +```