How do I break subevents list executing?

Hi all! I have an event with two subevents.

First subevent checks if variable is "1". If it's "1" subevent doing some actions and set this variable to "2".

The problem is that next subevent checks if variable is "2".

But it always executing because first subevent set variable to "2".

Is there any way to stop running subevents if one of them is executed?

Or any other logic to do what i described?

I need something like: if (variable is "1") 'do something, set variable to "2"' else 'do something'.

Thank you!

Thanks a lot!