Bubble Sort in Python: A Step-by-Step Guide

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Let’s break down the bubble sort algorithm with clear examples and code implementation in Python. This guide helps you understand the logic and implementation of bubble sort in a concise, easy-to-follow manner.

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Let’s take a list of 5 numbers and sort it step-by-step using the bubble sort algorithm.

[4, 2, 5, 3, 1]

Bubble sort works by pushing the largest element to the end of the list with each iteration, much like a bubble rising to the surface of water — an easy analogy to remember.

Round 1

First Comparison (4 and 2):

• Elements: 4 and 2
• Action: Swap (since 4 > 2)
• Updated List: [2, 4, 5, 3, 1]

Second Comparison (4 and 5):

• Elements: 4 and 5
• Action: No Swap (since 4 < 5)
• List Remains: [2, 4, 5, 3, 1]

Third Comparison (5 and 3):

• Elements: 5 and 3
• Action: Swap (since 5 > 3)
• Updated List: [2, 4, 3, 5, 1]

Fourth Comparison (5 and 1):

• Elements: 5 and 1