Python: Sort unsorted numbers using Recursive Quick Sort

Last update on April 23 2025 12:50:07 (UTC/GMT +8 hours)

28. Recursive Quick Sort

Write a Python program to sort unsorted numbers using Recursive Quick Sort.

Quicksort is a divide and conquer algorithm. It first divides the input array into two smaller sub-arrays: the low elements and the high elements. It then recursively sorts the sub-arrays.

Sample Solution:

Python Code:

def quick_sort(nums: list) -> list:
    if len(nums) <= 1:
        return nums
    else:
        return (
            quick_sort([el for el in nums[1:] if el <= nums[0]])
            + [nums[0]]
            + quick_sort([el for el in nums[1:] if el > nums[0]])
        )
nums = [4, 3, 5, 1, 2]
print("\nOriginal list:")
print(nums)
print("After applying Recursive Quick Sort the said list becomes:")
print(quick_sort(nums))
nums = [5, 9, 10, 3, -4, 5, 178, 92, 46, -18, 0, 7]
print("\nOriginal list:")
print(nums)
print("After applying Recursive Quick Sort the said list becomes:")
print(quick_sort(nums))
nums = [1.1, 1, 0, -1, -1.1, .1]
print("\nOriginal list:")
print(nums)
print("After applying Recursive Quick Sort the said list becomes:")
print(quick_sort(nums))

Sample Output:

Original list:
[4, 3, 5, 1, 2]
After applying Recursive Quick Sort the said list becomes:
[1, 2, 3, 4, 5]

Original list:
[5, 9, 10, 3, -4, 5, 178, 92, 46, -18, 0, 7]
After applying Recursive Quick Sort the said list becomes:
[-18, -4, 0, 3, 5, 5, 7, 9, 10, 46, 92, 178]

Original list:
[1.1, 1, 0, -1, -1.1, 0.1]
After applying Recursive Quick Sort the said list becomes:
[-1.1, -1, 0, 0.1, 1, 1.1]

Flowchart:

For more Practice: Solve these Related Problems:

Write a Python program to implement quick sort recursively and print the pivot at each recursion level.
Write a Python script to perform recursive quick sort on a list and then output the sorted list along with recursion depth.
Write a Python program to modify recursive quick sort to choose the median as the pivot and compare the number of comparisons.
Write a Python function to implement recursive quick sort on a list of strings and ensure the sort is case-insensitive.

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Previous: Write a Python program to sort unsorted numbers using Stooge sort.
Next: Write a Python program to sort a given collection of numbers and its length in ascending order using Recursive Insertion Sort.

Python Code Editor:

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