Add Merge Sort Algorithm Implementation

[mudassir0002]

Objective:
I would like to contribute to this repository by adding the code implementation of the Merge Sort algorithm in Python. Merge Sort is a well-known and efficient sorting algorithm with a time complexity of O(n log n). It operates by dividing the array into halves, recursively sorting them, and then merging the sorted halves together.

Implementation Details:
The function will take an unsorted list as input and return a sorted list using the merge sort technique. The implementation will ensure that it meets the standard coding guidelines of the repository.

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Input:

• A list of integers, arr, where:
  • 1 ≤ len(arr) ≤ 10^5
  • -10^9 ≤ arr[i] ≤ 10^9

Output:

• A list of integers sorted in non-decreasing order.

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Example Test Case:

Input:

arr = [38, 27, 43, 3, 9, 82, 10]

Output:

[3, 9, 10, 27, 38, 43, 82]

Constraints:

• The function must run in O(n log n) time complexity where n is the number of elements in the array.
• Auxiliary space must be kept minimal.

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Request for Label:
Please assign the Hacktoberfest label to this issue to indicate that this contribution is part of Hacktoberfest 2024.

Additional Request:
Once the issue is approved, kindly assign it to me so I can begin working on it.

Thank you for considering this contribution!

[Satyam-nitp]

Can you assign it to me @harsh-dart

[RaheelaTabassum]

please assign it to me

[aryaman0406]

Hi @harsh-dart please assign me this task.

[Blacksujit]

/assign

[Blacksujit]

Link to PR --> #110

[Smriti-Prajapati]

Hey please assign this issue to me for Hactoberfest 2024.