SOURCE

const arrOne = [1, 2, 3];
const arrTwo = [2, 3, 4, 5, 6];
// 数组的交集
const intersectionFn = (arr1, arr2) => {
    const result = arr1.filter(item1 => arr2.some(item2 => item1 === item2));
    console.log('交集', result);
    return result;
}
intersectionFn(arrOne, arrTwo);
// 数组的补集
const complementFn = (arr1, arr2) => {
    const result = arr1.filter(item1 => arr2.every(item2 => item1 !== item2));
    console.log('补集', result);
    return result;
}
complementFn(arrOne, arrTwo);
// 数组的并集
const unionFn = (arr1, arr2) => {
    const result = arr1.filter(item1 => arr2.every(item2 => item1 !== item2)).concat(arr2);
    console.log('并集', result);
    return result;
}
unionFn(arrOne, arrTwo);