Algorithms

Repeatedly swap adjacent out-of-order pairs; stop early when a pass makes no swap — O(n²).

Version 1.2.0 · current Versions: 1.2.0 1.1.0 1.0.0

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README.md
# Bubble Sort

Zerethon Official Sample `bubble-sort`, version 1.2.0, Python 3.12.

- `bubble_sort.py` — the algorithm, as shown in Zerethon Tools
- `main.py` — entry file: a short demonstration
- `test_bubble_sort.py` — checks; set it as the entry file to run them

This project is your own copy. Changing it never changes the official sample.
See the algorithm animated: https://tools.zerethon.com/bubble-sort-visualizer
bubble_sort.py
"""Bubble Sort (Zerethon Official Sample: bubble-sort 1.2.0)."""


def bubble_sort(a):
    n = len(a)
    for i in range(n - 1):
        swapped = False
        for j in range(n - 1 - i):
            if a[j] > a[j + 1]:
                a[j], a[j + 1] = a[j + 1], a[j]
                swapped = True
        if not swapped:  # already sorted
            break
    return a
main.py entry
from bubble_sort import bubble_sort

numbers = [38, 27, 43, 3, 9, 82, 10, 27]
print("Before:", numbers)
result = bubble_sort(list(numbers))
print("After: ", result)
print("Same as sorted():", result == sorted(numbers))
test_bubble_sort.py
# Checks for bubble_sort. To run them, set this file as the entry file
# (the ▶ button next to it in Files) and press Run.
from bubble_sort import bubble_sort


def numbers(seed, count):
    """Deterministic pseudo-random integers in [-50, 49]."""
    out = []
    for _ in range(count):
        seed = (seed * 1103515245 + 12345) % 2**31
        out.append(seed % 100 - 50)
    return out


cases = [[], [1], [2, 1], [1, 2, 3], [3, 2, 1], [5, 1, 5, 1, 5], [-3, 0, -1, 2]]
cases += [numbers(seed, size) for seed, size in ((1, 10), (2, 50), (3, 200))]

for case in cases:
    got = bubble_sort(list(case))
    assert got == sorted(case), f"bubble_sort({case[:6]}...) = {got[:6]}..."

print(f"All {len(cases)} checks passed.")

Source: Zerethon Official Sample. Algorithm as shown in the Zerethon Tools Bubble Sort Visualizer.