Alger logo
𝔸𝕝𝕘𝕖𝕣
About

Cycle Sort

"""
Code contributed by Honey Sharma
Source: https://en.wikipedia.org/wiki/Cycle_sort
"""


def cycle_sort(array: list) -> list:
    """
    >>> cycle_sort([4, 3, 2, 1])
    [1, 2, 3, 4]

    >>> cycle_sort([-4, 20, 0, -50, 100, -1])
    [-50, -4, -1, 0, 20, 100]

    >>> cycle_sort([-.1, -.2, 1.3, -.8])
    [-0.8, -0.2, -0.1, 1.3]

    >>> cycle_sort([])
    []
    """
    array_len = len(array)
    for cycle_start in range(0, array_len - 1):
        item = array[cycle_start]

        pos = cycle_start
        for i in range(cycle_start + 1, array_len):
            if array[i] < item:
                pos += 1

        if pos == cycle_start:
            continue

        while item == array[pos]:
            pos += 1

        array[pos], item = item, array[pos]
        while pos != cycle_start:
            pos = cycle_start
            for i in range(cycle_start + 1, array_len):
                if array[i] < item:
                    pos += 1

            while item == array[pos]:
                pos += 1

            array[pos], item = item, array[pos]

    return array


if __name__ == "__main__":
    assert cycle_sort([4, 5, 3, 2, 1]) == [1, 2, 3, 4, 5]
    assert cycle_sort([0, 1, -10, 15, 2, -2]) == [-10, -2, 0, 1, 2, 15]
Algerlogo

© Alger 2022

About us

We are a group of programmers helping each other build new things, whether it be writing complex encryption programs, or simple ciphers. Our goal is to work together to document and model beautiful, helpful and interesting algorithms using code. We are an open-source community - anyone can contribute. We check each other's work, communicate and collaborate to solve problems. We strive to be welcoming, respectful, yet make sure that our code follows the latest programming guidelines.