GroupBy.js

// Ask by TRUEIGTECH Company (23-05-2026)

// Q. you need to make a group of this array department wise
// A. {
//   Engineering: [
//     { id: 1, name: "Aashima", department: "Engineering" },
//     { id: 3, name: "Rahul", department: "Engineering" }
//   ],
//   Design: [
//     { id: 2, name: "Muskan", department: "Design" },
//     { id: 5, name: "Neha", department: "Design" }
//   ],
//   HR: [
//     { id: 4, name: "Priya", department: "HR" }
//   ]
// }

const users = [
    { id: 1, name: "Aashima", department: "Engineering", },
    { id: 2, name: "Muskan", department: "Design" },
    { id: 3, name: "Rahul", department: "Engineering", },
    { id: 4, name: "Priya", department: "HR" },
    { id: 5, name: "Neha", department: "Design" }
];

// Solutions 1:
// used - Custom Logic
function solution1(users) {
    let obj = {};

    for (let ele of users) {
        if (Object.keys(obj).includes(ele.department)) {
            obj[ele.department].push(ele);
        } else {
            obj[ele.department] = [ele];
        }

    };

    return obj;
}

const result1 = solution1(users);
console.log('result1 => ', result1)



// Solutions 2: 
// used in-built Object.groupBy() method
function solution2(users) {
    return Object.groupBy(users, (ele) => ele.department);
}

const result2 = solution2(users);
console.log('result2 => ', result2)


// Solutions 3:
// Different Custom Logic
function solution3(users) {

    let obj = {};

    for (let ele of users) {

        let department = ele.department;

        if (!obj[department]) {
            obj[department] = []
        }

        obj[department].push(ele);

    }
    return obj;
}

const result3 = solution3(users);
console.log('result3 => ', result3)