Radix Sort in python

algorithms/ar-radsrt/python2/radix_sort.py

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+# Function to get the maximum value in the list
+def getMax(arr):
+    max_val = arr[0]
+    for i in arr:
+        if i > max_val:
+            max_val = i
+    return max_val
+
+# Counting sort to sort elements based on the significant digit
+def countingSort(arr, exp):
+    n = len(arr)
+    output = [0] * n  # Output array to hold sorted elements
+    count = [0] * 10  # Initialize counting array (for base 10 digits)
+
+    # Store the count of occurrences
+    for i in range(n):
+        index = (arr[i] // exp) % 10
+        count[index] += 1
+
+    # Change count[i] so that count[i] contains the actual position
+    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) % 10
+        output[count[index] - 1] = arr[i]
+        count[index] -= 1
+        i -= 1
+
+    # Copy the output array to arr
+    for i in range(n):
+        arr[i] = output[i]
+
+# Main function to implement Radix Sort
+def radixSort(arr):
+    # Find the maximum number to determine the number of digits
+    max_val = getMax(arr)
+    # Do counting sort for every digit
+    exp = 1
+    while max_val // exp > 0:
+        countingSort(arr, exp)
+        exp *= 10
+
+# Example usage
+arr = [170, 45, 75, 90, 802, 24, 2, 66]
+print("Original array:", arr)
+radixSort(arr)
+print("Sorted array:", arr)
+