Implement Counting Sort in Python

algorithms/python/CountingSort.py

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+# Counting sort is a non-comparison sorting algorithm that works well when the range of values in the input array is small.
+# It works by counting the number of occurrences of each element in the input array and then using this information to construct
+# the sorted output array.
+
+# 💡 [ Time Complexity: O(n + k), where n is the number of elements in the input array and k is the range of input. ]
+
+def counting_sort(arr):
+    # Find the maximum and minimum values in the input array
+    max_val = max(arr)
+    min_val = min(arr)
+
+    # Create a counting array to store the count of each distinct element
+    count = [0] * (max_val - min_val + 1)
+
+    # Count the occurrences of each element in the input array
+    for num in arr:
+        count[num - min_val] += 1
+
+    # Reconstruct the sorted array from the counting array
+    sorted_arr = []
+    for i in range(len(count)):
+        while count[i] > 0:
+            sorted_arr.append(i + min_val)
+            count[i] -= 1
+
+    return sorted_arr
+
+
+def main():
+    input_arr = [4, 2, 2, 8, 3, 3, 1]  # example input array
+    sorted_arr = counting_sort(input_arr)  # sort the input array
+    print(sorted_arr)  # print the sorted array
+
+
+if __name__ == '__main__':
+    main()