code to get multiple unique elements from js list code example

Example 1: how to find unique elements in array in javascript

let a = ["1", "1", "2", "3", "3", "1"];
let unique = a.filter((item, i, ar) => ar.indexOf(item) === i);
console.log(unique);

Example 2: find unique values between multiple array

var array3 = array1.filter(function(obj) { return array2.indexOf(obj) == -1; });