npm i lodash
const _ = require('lodash'); // import the library using require
let departments = ["CSE","IT","CSE", "MECH"];
console.log("Departments:" , departments);
let uniqueDepartments = _.uniq ( departments);
console.log("Unique Department:", uniqueDepartments);
node departments.js
//output:
//Departments: [ 'CSE', 'IT', 'CSE', 'MECH' ]
//Unique Department: [ 'CSE', 'IT', 'MECH' ]