How Bubble Sort Works

Bubble sort is a simple sorting algorithm that repeatedly steps through the list, compares adjacent elements and swaps them if they are in the wrong order.

The pass through the list is repeated until the list is sorted. The algorithm gets its name because smaller elements "bubble" to the top of the list.

Key Characteristics:

Time Complexity: O(n²) in worst and average cases
Space Complexity: O(1) - it's an in-place sorting algorithm
Stable: Maintains relative order of equal elements
Not efficient for large datasets

Interactive Demonstration

Algorithm Steps:

Start at the beginning of the array
Compare the current element with the next element
If they are in wrong order, swap them
Move to the next pair
Repeat until no more swaps are needed

Implementation Details

function bubbleSort(arr) {
    let n = arr.length;
    let swapped;
    
    do {
        swapped = false;
        for (let i = 0; i < n - 1; i++) {
            // Compare adjacent elements
            if (arr[i] > arr[i + 1]) {
                // Swap if they are in wrong order
                [arr[i], arr[i + 1]] = [arr[i + 1], arr[i]];
                swapped = true;
            }
        }
        // After each pass, largest element bubbles to end
        n--;
    } while (swapped);
    
    return arr;
}

Optimization Tip

You can optimize by reducing the inner loop size after each pass since the largest elements bubble to the end.

When to Use

Only suitable for small datasets or nearly sorted data. For larger datasets, consider more efficient algorithms like quicksort or mergesort.