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Python Program for Bubble Sort

Bubble Sort is the simplest sorting algorithm that works by repeatedly swapping the adjacent elements if they are in the wrong order. 

Python Program for Bubble Sort

The provided Python code implements the Bubble Sort algorithm, which sorts an array by repeatedly comparing adjacent elements and swapping them if they are in the wrong order. The algorithm iterates through the array multiple times, with each pass pushing the largest unsorted element to its correct position at the end. The code includes an optimization: if no swaps are made during a pass, the array is already sorted, and the sorting process stops. The example initializes an array, applies the bubbleSort function to sort it, and prints the sorted array. After sorting, the output is: [11, 12, 22, 25, 34, 64, 90], indicating ascending order.

Python3
# Python program for implementation of Bubble Sort


def bubbleSort(arr):
    n = len(arr)
    # optimize code, so if the array is already sorted, it doesn't need
    # to go through the entire process
    # Traverse through all array elements
    for i in range(n-1):

        # range(n) also work but outer loop will
        # repeat one time more than needed.
        # Last i elements are already in place
        swapped = False
        for j in range(0, n-i-1):

            # traverse the array from 0 to n-i-1
            # Swap if the element found is greater
            # than the next element
            if arr[j] > arr[j + 1]:
                swapped = True
                arr[j], arr[j + 1] = arr[j + 1], arr[j]

        if not swapped:
            # if we haven't needed to make a single swap, we
            # can just exit the main loop.
            return


# Driver code to test above
arr = [64, 34, 25, 12, 22, 11, 90]

bubbleSort(arr)

print("Sorted array is:")
for i in range(len(arr)):
    print("% d" % arr[i], end=" ")

Output
Sorted array is:
 11  12  22  25  34  64  90 

Time Complexity:  O(n2).
Auxiliary Space: O(1).

Please refer complete article on Bubble Sort for more details! 

Python3
def bubblesort(elements):
    # Looping from size of array from last index[-1] to index [0]
    for n in range(len(elements)-1, 0, -1):
        swapped = False
        for i in range(n):
            if elements[i] > elements[i + 1]:
                swapped = True
                # swapping data if the element is less than next element in the array
                elements[i], elements[i + 1] = elements[i + 1], elements[i]
        if not swapped:
            # exiting the function if we didn't make a single swap
            # meaning that the array is already sorted.
            return

elements = [39, 12, 18, 85, 72, 10, 2, 18]

print("Unsorted list is,")
print(elements)
bubblesort(elements)
print("Sorted Array is, ")
print(elements)

Output
Unsorted list is,
[39, 12, 18, 85, 72, 10, 2, 18]
Sorted Array is, 
[2, 10, 12, 18, 18, 39, 72, 85]

Time Complexity:  O(n2). However in practice, this optimized version might take less time as when array gets sorted, function would return.
Auxiliary Space: O(1).

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