JSFiddle - React, Tailwind, and code Playground

by qiangtou

JavaScript

var a = [5, 1, 2, 3];
var b = [1, 3, 4];

var i, arr = [];
for (i = 0, len = a.length; i < len; i++) {
    arr[a[i]] = a[i];
}
for (i = 0, len = b.length; i < len; i++) {
    if (arr[b[i]]) {
        delete arr[b[i]];
        delete b[i];
    }
}

console.log('减少的',arr);
console.log('新增的',b);