Generate All Subsets Powerset in DSA Typescript - Build from Scratch

Generate All Subsets (Powerset)

📖 Scenario: Imagine you have a small collection of unique items, like three different colored marbles. You want to find all the possible groups you can make from these marbles, including the empty group and the group with all marbles.

🎯 Goal: Build a TypeScript program that takes a list of unique numbers and generates all possible subsets (the powerset) of that list.

📋 What You'll Learn

Create an array called nums with the exact values [1, 2, 3].

Create a variable called result to hold all subsets, starting with an empty subset.

Use a for loop to go through each number in nums.

Inside the loop, use another for loop to add the current number to existing subsets and add these new subsets to result.

Print the final result array showing all subsets.

💡 Why This Matters

🌍 Real World

Generating all subsets is useful in situations like choosing combinations of items, testing all possible feature sets in software, or exploring different groupings in data analysis.

💼 Career

Understanding how to generate powersets helps in problem solving, algorithm design, and is often asked in coding interviews for software engineering roles.

1

Create the initial array

Create an array called nums with the exact values [1, 2, 3].

DSA Typescript

# Create the array nums with values [1, 2, 3]
// Your code here

Hint

Use const nums = [1, 2, 3]; to create the array.

2

Create the result array with an empty subset

Create a variable called result and set it to an array containing an empty array [[]] to start with the empty subset.

DSA Typescript

const nums = [1, 2, 3];
// Create result array with an empty subset
// Your code here

Hint

Use const result: number[][] = [[]]; to start with an empty subset.

3

Generate all subsets using loops

Use a for loop with variable num to go through nums. Inside it, use another for loop with variable i to go through result. For each subset at index i, create a new subset by adding num to it and add this new subset to result.

DSA Typescript

const nums = [1, 2, 3];
const result: number[][] = [[]];
// Use nested loops to generate all subsets
// Your code here

Hint

Use for (const num of nums) and inside it for (let i = 0; i < length; i++). Add new subsets with result.push([...curr, num]).

4

Print the final result

Print the result array to show all subsets.

DSA Typescript

const nums = [1, 2, 3];
const result: number[][] = [[]];
for (const num of nums) {
    const length = result.length;
    for (let i = 0; i < length; i++) {
        const curr = result[i];
        result.push([...curr, num]);
    }
}
// Print the result array
// Your code here

Hint

Use console.log(result); to print all subsets.