I have a string like this:
Let's say I want to delete the 18 out of the string so it's like this:
What would be a good way to do that?
Also I need to do an add but only if the number is not already in the string,
So I have
And I try to add 18
it should fail because 18 is already there but if I try and add 9 it will add it on
12,18,4,9 (I already got this part working)