added radix sort program

Author: thatsabhishek

README.md

@@ -36,6 +36,7 @@ In case, the list becomes too big in the future you can use `cmd + f` or `ctrl +
   - [Insertion Sort](./sorting/insertionsort.py)
   - [Merge Sort](./sorting/mergesort.py)
   - [Quick Sort](./sorting/quicksort.py)
+  - [Radix Sort](./sorting/radixsort.py)
   - [Selection Sort](./sorting/selectionsort.py)
 - [Other Programs](./otherprograms)
   - [Armstrong number or not](./otherprograms/armstrongnumber.py)

sorting/radixsort.py

@@ -0,0 +1,48 @@
+def radix_sort(arr):
+    # Find the maximum number to determine the number of digits
+    max_num = max(arr)
+    
+    # Perform counting sort for every digit
+    exp = 1
+    while max_num // exp > 0:
+        counting_sort(arr, exp)
+        exp *= 10
+
+def counting_sort(arr, exp):
+    n = len(arr)
+    output = [0] * n
+    count = [0] * 10
+
+    # Store the count of each digit in count[]
+    for i in range(n):
+        index = arr[i] // exp
+        count[index % 10] += 1
+
+    # Change count[i] so that count[i] contains the actual position
+    # of this digit in output[]
+    for i in range(1, 10):
+        count[i] += count[i - 1]
+
+    # Build the output array
+    i = n - 1
+    while i >= 0:
+        index = arr[i] // exp
+        output[count[index % 10] - 1] = arr[i]
+        count[index % 10] -= 1
+        i -= 1
+
+    # Copy the output array to arr[] so that arr[] contains sorted numbers
+    for i in range(n):
+        arr[i] = output[i]
+
+# Enter user inputs in an array
+n = int(input("Enter the number of elements: "))
+arr = []
+for i in range(n):
+    a = int(input("Enter element: "))
+    arr.append(a)
+print()
+
+print("Unsorted Array:", arr)
+radix_sort(arr)
+print("Sorted array:", arr)