I would like to see your solution, but i couldnt find it. Cheers!

but I wanted to complicate the problem even more

That's not really the right way to "complicate the problem". Please give us actual, good difficulty instead of fake difficulties that doesn't really pose as a useful challenge.

You're right about that too :) But I need help. I am new here. I don't know how to do it. I liked this place very much, I solved many questions, and I learned a lot. I wanted to make a small contribution. :)

Yes you are right but I wanted to complicate the problem even more.
For example input:[...3,4,3...].
Output: Expected to be [..3..].
The number 3 should not be printed twice. So I thought that those who solved the question would also use set logic.

There are only small fixed tests in the test fixture ;-)

Please add randomly generated tests (and probably performance tests too, since that's sort of the point).

Input numbers can have duplicates, but returned result should not be a repeating number, which are contradictory with each other. Why not deduplicate the input before passing in (or better, pass in Set<Integer>)?

I was enlightened when I saw this solution. thanks bro :)

You're right. I am sorry. not again.

And it should be the same for everyone, one must not solve a kata looking at Discourse. I marked your kata as a spoiler. Please don't do it again.

I couldn't figure it out without using a nested loop.

I had a hard time solving it, but I finally solved it. I felt stupid when I saw the best solution in the answers section. indeed, it has a simple solution, but I used too many unnecessary things.

I pass the test but I cannot pass the attempt. :(