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Correcting a bug in the merge sort algorithm

You have been given a program that sorts a list of numbers using the merge sort algorithm. While testing the merge_sort() function, you realize that the code is not correct. Can you correct the algorithm so that it works correctly?

Questo esercizio fa parte del corso

Data Structures and Algorithms in Python

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Istruzioni dell'esercizio

  • Correct the mistake when assigning the left half.
  • Correct the mistake when assigning the right half.
  • Correct the mistake when updating the pointer for the left half.
  • Correct the mistake when updating the pointer for the right half.

Esercizio pratico interattivo

Prova a risolvere questo esercizio completando il codice di esempio.

def merge_sort(my_list):
    if len(my_list) > 1: 
        mid = len(my_list)//2
        left_half = my_list[:mid]
        right_half = my_list[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]:
        		# Correct mistake when assigning left half
                my_list[k] = right_half[i]                
                i += 1
            else:
                # Correct mistake when assigning right half
                my_list[k] = left_half[j]
                j += 1
            k += 1
            
        while i < len(left_half):
            my_list[k] = left_half[i]
            # Correct mistake when updating pointer for left half
            j += 1
            k += 1
 
        while j < len(right_half):
            my_list[k] = right_half[j]
            # Correct mistake when updating pointer for right half
            i += 1
            k += 1

my_list = [35,22,90,4,50,20,30,40,1]
merge_sort(my_list)
print(my_list)
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