Given an array of integers, remove the n smallest – Codewars, Python

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My code fails the tests part of the question given below,
Q: Given an array of integers, remove the n smallest. If there are multiple elements with the same value, remove the ones with a lower index first. If n is greater than the length of the array/list, return an empty list/array. If n is zero or less, return the original array/list.
Don’t change the order of the elements that are left.

And here is my attempt:

def remove_smallest(n, arr):
    if n > 0:
        smallest_nums = sorted(arr)[:n]
        return [x for x in arr if x not in smallest_nums]
    return arr

I am not able to figure out the reason why my code does not work, it manages to pass all the basic 7 tests when I test the code, but when I try to attempt, my code fails quite a few of the random tests. The arrays used in the random tests are very huge, and I am not sure how to use them to find out where I went wrong. Any sort of advice that will help me debug the code by providing some techniques will be really helpful, Thank you.

>Solution :

The problem is that your return statement takes values that are not in that smallest_nums, but that could be filtering away too much. Some occurrences of the maximum value in that smallest_nums might still need to stay in the list.

Here is a minimal input for which your code fails:

print(remove_smallest(1, [1, 1]))

This prints an empty list, but it should print [1].

So you’ll need to take into account how many of that maximum value are in the original input and how many you have put in the smallest_nums and leave the difference in arr.

If you need a spoiler, here is your code adapted with that fix:

def remove_smallest(n, arr):
if n > 0 and arr:
smallest_nums = sorted(arr)[:n]
greatest = smallest_nums[-1]
count = len(smallest_nums) - smallest_nums.index(greatest)
return [x for x in arr
if x not in smallest_nums
or (x == greatest and (count := count - 1) < 0)]
return arr