数组的交集并集差集

Code

// 两个数组的并集、交集、差集
// 不能出现重复项，得到的结果是一个新数组
const arr1 = [33, 22, 22, 55, 33, 11, 33, 5];
const arr2 = [22, 22, 55, 77, 88, 88, 99, 99];

解析

// 并集
const union = Array.from(new Set([...arr1, ...arr2]));

// 交集
const cross = Array.from(new Set(arr1.filter(x => arr2.includes(x))));

// 差集
const diff = Array.from(new Set(union.filter(x => !cross.includes(item))));