Python: Sort a list of elements using Radix sort

Last update on April 23 2025 12:50:11 (UTC/GMT +8 hours)

19. Radix Sort

Write a Python program to sort a list of elements using Radix sort.
According to Wikipedia "In computer science, radix sort is a non-comparative integer sorting algorithm that sorts data with integer keys by grouping keys by the individual digits which share the same significant position and value".

Sample Solution:

Python Code:

def radix_sort(nums):
    RADIX = 10
    placement = 1
    max_digit = max(nums)

    while placement < max_digit:
      buckets = [list() for _ in range( RADIX )]
      for i in nums:
        tmp = int((i / placement) % RADIX)
        buckets[tmp].append(i)
      a = 0
      for b in range( RADIX ):
        buck = buckets[b]
        for i in buck:
          nums[a] = i
          a += 1
      placement *= RADIX
    return nums
user_input = input("Input numbers separated by a comma:\n").strip()
nums = [int(item) for item in user_input.split(',')]
print(radix_sort(nums))

Sample Output:

Input numbers separated by a comma:
 15, 79, 25, 68, 37
[15, 25, 37, 68, 79]

Flowchart:

For more Practice: Solve these Related Problems:

Write a Python program to implement radix sort for a list of non-negative integers and display the intermediate digit groupings.
Write a Python script to sort a list of integers using radix sort and then print the sorted output along with the number of passes made.
Write a Python program to modify radix sort to sort a list of strings representing numbers and then compare the results with numerical sorting.
Write a Python function to implement radix sort and then validate the sorted list against Python’s built-in sorted() function.

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