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Computer Science Introduction to Data Structures The Merge Sort Algorithm Ensuring the Correctness of Merge Sort

Posted by liamthornback2
liamthornback2
9,618 Points

Shouldn't the test condition of the verify_sort function be "equal to or less than"?

This is what my verify_sorted function looks like:

def verify_sorted(list):
  n = len(list)

  if n == 0 or n == 1:
    return True

  return list[0] <= list[1] and verify_sorted(list[1:])

I found that the function would sometimes return False even if the list was actually sorted if there were duplicate numbers.

Brandon Little
Brandon Little
30,417 Points
Brandon Little
Brandon Little
30,417 Points

I experienced the same issue, and made the same change.

1 Answer

Victor Cooke
Victor Cooke
35,162 Points
Victor Cooke
Victor Cooke
35,162 Points

I believe it should be a <= instead of < as well