Bubble Sort

The simplest sorting algorithm that works by repeatedly swapping adjacent elements if they are in the wrong order. Named “bubble sort” because smaller elements “bubble” to the top.

Algorithm

Basic Bubble SortOptimized Bubble Sort

Controls

Array Size

Speed: 1000ms

Statistics

Pass:0

Comparisons:0

Swaps:0

Array Size:0

Complexity

Time Complexity:

Best:O(n)

Average:O(n²)

Worst:O(n²)

Space Complexity:

O(1)In-place sorting

Properties:

Stable

In-place

Adaptive*

*Only optimized version

Array Visualization

Pass 0 - Ready

Unsorted

Comparing

Swapping

Sorted

How Bubble Sort Works:

Basic Algorithm:

Compare adjacent elements
Swap if they are in wrong order
Continue through the array
Repeat until no swaps needed

Optimization:

Track if any swaps occurred in a pass
If no swaps, array is sorted
Reduces best-case to O(n)
Still O(n²) in average/worst case

Implementation

Basic Bubble Sort

function bubbleSort(arr) {
  const 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 elements
        [arr[j], arr[j + 1]] = [arr[j + 1], arr[j]];
      }
    }
  }
  
  return arr;
}

// Time: O(n²), Space: O(1)

Optimized Bubble Sort

function optimizedBubbleSort(arr) {
  const n = arr.length;
  
  for (let i = 0; i < n - 1; i++) {
    let hasSwapped = false;
    
    for (let j = 0; j < n - i - 1; j++) {
      if (arr[j] > arr[j + 1]) {
        // Swap elements
        [arr[j], arr[j + 1]] = [arr[j + 1], arr[j]];
        hasSwapped = true;
      }
    }
    
    // If no swaps, array is sorted
    if (!hasSwapped) break;
  }
  
  return arr;
}

// Best case: O(n), Worst: O(n²)

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