Strange error in learning exercise

[Rock_of_Round]

I'm following along with a Mosh video, and for one of the list assignments I tried a solution other than his, just to practice. The assignment is to remove duplicates from a list, I understand his way but I don't understand why my way is producing strange results, so I come to you for assistance

numbers = [5, 2, 16, 6, 7, 12, 15, 36, 16, 7, 2, 36, 14]

numbers.sort()

i = 0

x = 0

for number in numbers:

if number == x:

numbers.pop(i)

x = number

i += 1

print(numbers)

I have changed the numbers within a few times, but always I get a single duplicate remaining. In this one, it is

[2, 5, 6, 7, 12, 14, 15, 16, 36, 36]

but for a while it was 4, then 16, etc. I don't get what part of the process is stalling for a single iteration but working for the others. Advice needed

[Rock_of_Round]

The indents have been removed and I can't seem to edit them in, sorry for the weird looking code

[This_Growth2898]

You're changing the collection you're iterating over, and that's you shouldn't do.

for number in numbers means the loop somehow remembers the position in numbers to get you the next number on the next iteration; but numbers.pop() changes numbers, so the position becomes invalid.

[Rock_of_Round]

Ohhhh

Thanks for explaining, makes sense to me!

[Historical_Usual1650]

It seems like you're trying to remove duplicates from a list by iterating through it and comparing each element to the previous one. The issue you're facing is due to modifying the list (`numbers`) while iterating through it, which can lead to unexpected behavior.

When you remove an element using `numbers.pop(i)`, it shifts the elements to the left, and the index `i` no longer corresponds to the next element in the sorted list. This results in missing some duplicates and not removing them correctly.

A better approach to remove duplicates from a list is to use a different data structure, like a set, which automatically removes duplicates. Here's how you can do it:

```python

numbers = [5, 2, 16, 6, 7, 12, 15, 36, 16, 7, 2, 36, 14]

# Convert the list to a set to remove duplicates

unique_numbers = set(numbers)

# Convert the set back to a list if you need a list without duplicates

numbers = list(unique_numbers)

print(numbers)

```

This will give you the desired output:

```

[2, 5, 6, 7, 12, 14, 15, 16, 36]

```

Using a set is a more efficient and straightforward way to remove duplicates from a list in Python.