How does the merge sort algorithm work?

How does the merge sort algorithm work?

Merge sort is a divide-and-conquer algorithm that splits an array into halves, sorts each half, and merges them back together.

Can you show me a simple implementation of merge sort in Python?

Sure! Here's a basic implementation:

def merge_sort(arr):
    if len(arr) > 1:
        mid = len(arr) // 2
        left_half = arr[:mid]
        right_half = arr[mid:]

        merge_sort(left_half)
        merge_sort(right_half)

        i = j = k = 0

        while i < len(left_half) and j < len(right_half):
            if left_half[i] < right_half[j]:
                arr[k] = left_half[i]
                i += 1
            else:
                arr[k] = right_half[j]
                j += 1
            k += 1

        while i < len(left_half):
            arr[k] = left_half[i]
            i += 1
            k += 1

        while j < len(right_half):
            arr[k] = right_half[j]
            j += 1
            k += 1

    return arr

What is the time complexity of merge sort?

The time complexity of merge sort is O(n log n) in the average and worst cases, making it efficient for large datasets.