Sorting algorithms play a crucial role in computer science as they allow us to organize large sets of data in a specific order. Whether it's sorting a list of names alphabetically or organizing data for efficient searching, sorting algorithms are fundamental tools that enable us to work with data more effectively.
One commonly used sorting algorithm is called Bubble Sort. It is a simple and intuitive algorithm that works by repeatedly swapping adjacent elements if they are in the wrong order, gradually moving the larger elements towards the end of the list. Let's take a closer look at how Bubble Sort works:
Imagine you have an unsorted list of numbers: [7, 3, 9, 2, 1]. The goal is to sort this list in ascending order.
Bubble Sort starts by comparing the first two elements of the list, 7 and 3. Since 3 is smaller than 7, we swap them, resulting in [3, 7, 9, 2, 1].
Next, we compare the second and third elements, 7 and 9. Since they are already in the correct order, we leave them as they are.
Moving on, we compare the third and fourth elements, 9 and 2. Again, since 2 is smaller, we swap them: [3, 7, 2, 9, 1].
Continuing this process, we compare 9 and 1 and swap them: [3, 7, 2, 1, 9].
This completes the first pass of Bubble Sort, with the largest element 9 being moved to its correct position at the end of the list.
Bubble Sort has a time complexity of O(n^2) in the average and worst case scenarios, where n represents the number of elements in the list.
To understand why Bubble Sort has this time complexity, consider that in each pass, Bubble Sort compares adjacent elements and swaps them if they are in the wrong order. The algorithm needs to iterate through the list multiple times until it no longer needs to make any swaps. On average, for a list of n elements, Bubble Sort performs about n/2 passes, resulting in n/2 comparisons and swaps per pass. This yields a time complexity of O(n^2).
However, worth noting is the best case scenario, where the list is already sorted. In this case, Bubble Sort performs only one pass, resulting in a time complexity of O(n).
So while Bubble Sort is simple to understand and implement, it may not be the most efficient sorting algorithm, especially for large lists. In the next post, we will dive deeper into the inner workings of Bubble Sort and explore its advantages and disadvantages.