Agree: why is it declared Clever why it doesn't solve the problem

Yes, Thanks !

Your function should return the first non-repeated char of the string, so, if the string has only 1 char, it should return that one. It's not repeated, is it? At least I think that's the way of understanding it.

Looks at the minimal test suite (in Python) :

test.assert_equals(first_non_repeating_letter('a'), 'a')

I may have misunderstood the point, so I've added a specific check on len(s) == 1 => return s

What are you saying there? 'a' is not repeated, so, yes, dups('a') => '' of course.

If a string contains all repeating characters, it should return an empty string ("");

dups('a') => '' and not 'a'

I don't understand why the "isdigit()" test work in your context.

Using Python 3.12 on my own computer:

a = "098"

b = "98"

print(a.isdigit()) => True => Here we want to reject it in the exercice

print(b.isdigit()) => True

What did I miss ? :/

EDIT : OK, I wasn't looking at the right part of the evaluation, it's "str(int(o))==o" who do the job :)

AHAHAHA !!

I disagree, this is against the main objective of this platform, which is to learn how to implement stuff.

What do we learn from this solution ? Nothing.

:D

This is smart move to consider the total sum of elements, but what if we have different numbers and their multiplicity while the sum is the same ? Is it possible ?

Ok, I just learned items of a list don't need to be ordered the same way to make an evaluation between 2 arrays.
(This will be invalid in PHP)