Multiple IF expression - Invalid type in operator == error

[Saarek]

I'm new to Alteryx and am trying to perform what should be a relatively simple task.

I have two existing columns, the rows in these columns contain either a 0 or a 1. The 0 denotes a no whilst the 1 denotes a yes.

I need a working formula that creates a new column based off of the following:

If the value in column A is 0 then mark as 0, if the value is 1 look at Column B, if Column B is a 0 then mark as 1, if Column B is a 1 mark as 0.

The formula I am trying to use is:

IF [Renewal_Invited_Count] =0 THEN "0" ELSEIF [Renewal_Lapsed_Count] =0 THEN "1" ELSE "0" ENDIF

Unfortunately this formula is bringing up the error listed in the title, the exact error message when run is: Error: Formula (105): Parse Error at char(0): Invalid type in operator ==. (Expression #5)

I'm sure that I have a simple syntax error, but for life of me cannot get it to work no matter which way I write it.

[AndrewW · Accepted solution]

Your formula looks good, I tried it on a sample dataset and it worked. You're returning a string field and I expect your source fields (Renewal_Invited_Count and Renewal_Lapsed_Count) are Byte or Int fields. Worth checking the field types and letting the forum know whether this could be an issue as your formula worked for me. 

[Saarek · Accepted solution]

Thanks for looking everyone, have realised my newbie mistake. The formula was just fine, except for the fact that my data is a vstring and as such I needed to place quotation marks around the 0's.