Implemented recursive merge sort algorithm with O(n log n) time complexity. (bregman-arie#10553)

Author: djeada

coding/python/merge_sort.py

@@ -0,0 +1,47 @@
+#!/usr/bin/env python
+
+import random
+from typing import List
+
+
+def merge_sort(arr: List[int]) -> List[int]:
+    if len(arr) <= 1:
+        return arr
+    mid = len(arr) // 2
+    left = merge_sort(arr[:mid])
+    right = merge_sort(arr[mid:])
+    return merge(left, right)
+
+
+def merge(left: List[int], right: List[int]) -> List[int]:
+    merged = []
+    i = j = 0
+    while i < len(left) and j < len(right):
+        if left[i] <= right[j]:
+            merged.append(left[i])
+            i += 1
+        else:
+            merged.append(right[j])
+            j += 1
+    merged.extend(left[i:])
+    merged.extend(right[j:])
+    return merged
+
+
+def generate_random_list(size: int = 10, lower: int = 1, upper: int = 100) -> List[int]:
+    return [random.randint(lower, upper) for _ in range(size)]
+
+
+def main():
+    """
+    Executes the merge sort algorithm with a randomly generated list.
+    Time Complexity: O(n log n)
+    """
+    rand_num_li = generate_random_list()
+    print(f"Unsorted List: {rand_num_li}")
+    sorted_list = merge_sort(rand_num_li)
+    print(f"Sorted List: {sorted_list}")
+
+
+if __name__ == '__main__':
+    main()