Understanding the Bubble Sort Algorithm in JavaScript

Understanding the Bubble Sort Algorithm in JavaScript

Overview

Bubble Sort is a straightforward sorting algorithm that iteratively steps through a list, comparing adjacent elements and swapping them if they are in the incorrect order. This process is repeated until the entire list is sorted.

Key Concepts

  • Sorting: The act of arranging items in a specific order, either ascending or descending.
  • Adjacent Elements: Elements that are next to each other in a list.
  • Swapping: The process of exchanging the positions of two elements.

How Bubble Sort Works

  1. Comparison: Start from the first element and compare it with the next element.
  2. Swap if Necessary: If the first element is greater than the second, swap them.
  3. Repeat: Move to the next pair of adjacent elements and repeat the comparison and swapping.
  4. Iterate: Continue this process for the entire list. After each complete pass through the list, the largest unsorted element "bubbles up" to its correct position.
  5. End Condition: The algorithm terminates when a complete pass occurs without any swaps, indicating that the list is sorted.

Example Implementation

Below is a simple JavaScript implementation of the Bubble Sort algorithm:

function bubbleSort(arr) {
    let n = arr.length;
    for (let i = 0; i < n - 1; i++) {
        for (let j = 0; j < n - i - 1; j++) {
            if (arr[j] > arr[j + 1]) {
                // Swap arr[j] and arr[j + 1]
                let temp = arr[j];
                arr[j] = arr[j + 1];
                arr[j + 1] = temp;
            }
        }
    }
    return arr;
}

// Example usage
let numbers = [64, 34, 25, 12, 22, 11, 90];
console.log(bubbleSort(numbers)); // Output: [11, 12, 22, 25, 34, 64, 90]

Advantages and Disadvantages

Advantages

  • Simplicity: It is easy to understand and implement.
  • No Additional Memory: The algorithm sorts the list in place, requiring no extra storage.

Disadvantages

  • Inefficiency: With a time complexity of O(n²), it is inefficient for large datasets compared to more advanced sorting algorithms like Quick Sort or Merge Sort.

Conclusion

Bubble Sort is a fundamental sorting technique that is particularly useful for educational purposes and for grasping the concepts of sorting algorithms. Although it is not ideal for large datasets, it provides a clear illustration of how sorting works.