You have to enter something that has an opposite and/or is applicable. It will then try to find if your input has an opposite. The opposites [in the code] are numbered so that it is easier for numbering what's new in the Updates Log. If you enter a number, it will give you the negative value of that number, if you enter a negative number, it will give you the positive value of that number, if your input contains letters (and/or other symbols) with numbers or hyphens (for negatives) then it will return zero to indicate that there is a NaN error. To simplify everything I just said, I basically made a super smart machine that will give you the opposite of what you answered, and can also even give you the opposite of numbers.
I made the entire thing by myself. I used XML code formatting for the blocks that I created. Updates Log: 1.0: first version 1.1: numbers 16-20
