sort

an array sorting algorithm in ascending order implemented in Python

def my_sort(arr: list) -> list:
  if len(arr) <= 1:
    return arr

Empty and single element arrays cannot be sorted. The array requires at least two elements.

pivot = arr[0]

Variable pivot stores the value of the first element. This algorithm must pivot the given array to the left (less than) or right (greater than) of the first element. For example, if pivot = 5, then all elements less than 5 must be pivoted to the left, else, they must be pivoted to the right.

left = [i for i in arr[1:] if i <= pivot]
right = [i for i in arr[1:] if pivot < i]

All elements less than the first element are pivoted to the left, else, they are pivoted to the right.

return my_sort(left) + [pivot] + my_sort(right)

Recursively sort the left and right arrays until they cannot be sorted, keep the pivot sandwiched between them (since all values to the right are greater than pivot, and all values to the left are less than or equal to pivot)