compare equal of two arrays javascript code example

Example 1: javascript get array difference

function arrayDiff (a1, a2) {
    var a = [], diff = [];
    for (var i = 0; i < a1.length; i++) {
        a[a1[i]] = true;
    }
    for (var i = 0; i < a2.length; i++) {
        if (a[a2[i]]) {
            delete a[a2[i]];
        } else {
            a[a2[i]] = true;
        }
    }
    for (var k in a) {
        diff.push(k);
    }
    return diff;
}
//usage:
console.log(arrayDiff(['red', 'white','green'], [ 'red','white', 'blue']));//["green", "blue"]

Example 2: comparing two arrays in javascript

const arr1 = [1, 2, 3];
const arr2 = [1, 3, 3];

if (arr1.length !== arr2.length) return console.log("false");
for (let i = 0; i < arr1.length; i++) {
    for (let j = 0; j < arr2.length; j++) {
        if (arr1[i] === arr2[j]) {
            console.log("yes match", arr1[i], arr2[j]);
            continue;
        }
        console.log("no match", arr1[i], arr2[j]);
    }
}