👀 Views: 57 💬 Answers: 1 📅 Created: 2025-07-05

python algorithm merge-sort recursion Python

Can someone help me understand I need help solving I'm implementing the Merge Sort algorithm in Python 3.9, and I'm running into a stack overflow behavior when sorting large datasets... My implementation seems correct, but I'm not sure if I'm exceeding the recursion depth allowed by Python. Here’s the code I wrote: ```python def merge_sort(arr): if len(arr) > 1: mid = len(arr) // 2 # Finding the mid of the array left_half = arr[:mid] # Dividing the elements into 2 halves right_half = arr[mid:] merge_sort(left_half) # Sorting the first half merge_sort(right_half) # Sorting the second half i = j = k = 0 # Copy data to temp arrays L[] and R[] 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 # Checking if any element was left 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 my_list = [i for i in range(100000)] # Large dataset merge_sort(my_list) ``` When I run this code with a list containing 100,000 elements, I get a `RecursionError: maximum recursion depth exceeded in comparison`. I understand that Python's default recursion limit is relatively low (around 1000). I tried increasing the recursion limit using `sys.setrecursionlimit()` but still received the same behavior. I also considered changing the algorithm to an iterative version, but I'd like to understand why my current recursive implementation fails. Has anyone encountered this scenario with Merge Sort or can provide insights on how to resolve the recursion depth question for large datasets? I'm using Python 3.11 in this project. Could this be a known issue? For context: I'm using Python on Windows 11. What am I doing wrong?