new: adding challenge template for merge sort -@iamserda

Author: iamserda

neetcodeio/algostructybeginners/Lv3-Sorting/merge_sort_challenge.py

@@ -0,0 +1,12 @@
+import math
+
+
+def merge_sort(arr):
+    pass
+
+
+arr1 = [11, 3, 5, 7, 0, 2, 4, -5, 7, 8]
+arr2 = sorted(arr1)
+arr3 = merge_sort(arr1)
+print(arr3)
+assert arr3 == arr2