Bubble Sort in Python

annlin profile image ann lin ・1 min read

Become a Software Engineer -> Pass Technical Interview -> Be darn good at Data Structure and Algorithms -> Starting with Sorting Algorithms -> 1. Bubble Sort

Bubble Sort (Decreasing Order)

def bubblesort(array):
    # we minus 1 because we are always comparing the current value with the next value
    lengthOfArray = len(array) - 1
    # numbe of rounds will be the total length - 1, for array with length 5, we will do 4 rounds: 0 and 1, 1 and 2, 2 and 3, 3 and 4.
    for i in range(lengthOfArray):
        # at each round, we compare the current j with the next value
        for j in range(lengthOfArray - i):
            # only swap their positions if left value < right value as we aim to move all the small values to the back
            if array[j] < array[j + 1]:
                array[j], array[j + 1] = array[j + 1], array[j]

    return array

array = [2, 1, 5, 4, 3]
print bubblesort(array)

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ann lin


I am a spider, I build web.


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The video is funny, good idea. Numbers are really boring.


aww thanks, took the chance to showcase my favourite people too :)


I want to see quick sort. When will you publish it?

Your wish is my command. Coming up soon :)

Thanks for caring, expecting..., :)