JAVASCRIPT

javascript check if elements of one array are in another

const found = arr1.some(r=> arr2.includes(r))

javascript check if array is subset of another

let superSet = ['B', 'C', 'A', 'D'];
let subSet = ['D', 'C'];
let mixedSet = new Set([...superSet, ...subSet]);
let isSubset = mixedSet.size == superSet.length