Limit User Input

[Vladamir]

I will eventually get around to building a UserForm to handle this but in the meantime I'd like to just write a formula which would do the following:

Almost all the cells we ask the user to fill in require only a "Y/N" answer. But in some instances, if they answer "Y" to a cell, there will be other cells which they must now answer as "N".

For example, If cell F12 is filled in with a "Y" then cell F18 which they have not gotten to yet can only be "N". And inversely, if they fill in cell F18 with a "Y" then cell F12 must be "N". The format is sort of in order so I would make it that cell F12 will be filled in first as they move down the list. And depending on how they answer cell F12 then cell F18 must limit itself to "N" only. Trickier that one would think.

[Leith Ross]

Hello Vladamir,

I don't think this can be done reliably using formulas. There is no way for you to control the order of evaluation. Excel has algorithms built-in to optimize the order in which the formulas are executed.