Selection Sort Algorithm in DSA Javascript - Build from Scratch

Selection Sort Algorithm

📖 Scenario: You have a list of numbers that you want to arrange from smallest to largest, like organizing books by height on a shelf.

🎯 Goal: Build a program that sorts a list of numbers using the selection sort method, which finds the smallest number and puts it in the right place step by step.

📋 What You'll Learn

Create an array called numbers with the exact values: [29, 10, 14, 37, 13]

Create a variable called n that stores the length of the numbers array

Use a for loop with variable i to iterate from 0 to n - 1

Inside the loop, create a variable called minIndex and set it to i

Use a nested for loop with variable j to iterate from i + 1 to n

Inside the nested loop, compare numbers[j] with numbers[minIndex] and update minIndex if a smaller number is found

After the nested loop, swap the values at numbers[i] and numbers[minIndex]

Print the sorted numbers array

💡 Why This Matters

🌍 Real World

Sorting helps organize data like names, scores, or prices so we can find or compare them easily.

💼 Career

Understanding sorting algorithms is important for software development, data analysis, and optimizing performance.

1

Create the initial array

Create an array called numbers with these exact values: [29, 10, 14, 37, 13]

DSA Javascript

// Create the array called numbers with the values [29, 10, 14, 37, 13]
// Your code here

Hint

Use const numbers = [29, 10, 14, 37, 13]; to create the array.

2

Set up the length variable

Create a variable called n that stores the length of the numbers array

DSA Javascript

const numbers = [29, 10, 14, 37, 13];
// Create a variable n that stores the length of numbers
// Your code here

Hint

Use const n = numbers.length; to get the array length.

3

Implement the selection sort loops

Use a for loop with variable i from 0 to n - 1. Inside it, create minIndex set to i. Then use a nested for loop with variable j from i + 1 to n. Inside the nested loop, if numbers[j] is less than numbers[minIndex], update minIndex to j. After the nested loop, swap numbers[i] and numbers[minIndex].

DSA Javascript

const numbers = [29, 10, 14, 37, 13];
const n = numbers.length;
// Write the selection sort loops and swapping logic below
// Your code here

Hint

Use two loops: outer loop with i, inner loop with j. Swap after finding the smallest number.

4

Print the sorted array

Print the numbers array after sorting using console.log(numbers)

DSA Javascript

const numbers = [29, 10, 14, 37, 13];
const n = numbers.length;

for (let i = 0; i < n - 1; i++) {
    let minIndex = i;
    for (let j = i + 1; j < n; j++) {
        if (numbers[j] < numbers[minIndex]) {
            minIndex = j;
        }
    }
    const temp = numbers[i];
    numbers[i] = numbers[minIndex];
    numbers[minIndex] = temp;
}
// Print the sorted numbers array
// Your code here

Hint

Use console.log(numbers) to show the sorted array.