What Is Bubble Sort?
Bubble sort is a simple sorting algorithm that repeatedly steps through a list, compares each pair of adjacent items, and swaps them if they are in the wrong order. This process of passing through the list is repeated until the list is fully sorted and no more swaps are needed.
Section 2: How It Works
The core principle of bubble sort is the 'pass.' During one pass, the algorithm moves from the beginning of the list to the end. With each step, it compares an element with the one next to it. If the first element is larger than the second, it swaps them. This effectively causes the largest unsorted element to 'bubble up' to its correct position at the end of the list with each pass.
Section 3: A Practical Example
Consider sorting the list [5, 1, 4, 2]. In the first pass: (5, 1) are swapped -> [1, 5, 4, 2]. Then, (5, 4) are swapped -> [1, 4, 5, 2]. Finally, (5, 2) are swapped -> [1, 4, 2, 5]. The first pass ends with 5 in its correct place. The next pass would sort the remaining [1, 4, 2], and so on, until the entire list is [1, 2, 4, 5].
Section 4: Importance and Limitations
Bubble sort is highly inefficient for large lists, with a time complexity of O(n²). However, it is very important in computer science education because its logic is simple to understand and implement. It provides a foundational understanding of how sorting algorithms work, serving as a building block for learning more efficient methods like merge sort or quicksort.