Dear all,

I'm working on a situation for making a rooming list, people sharing room.

I've around 60 classmate and some of them are going to share room with the
classmate. They change their mind so frequent, is annoying

I want to see how i can managed the change without any hassle.

I made use of their student number, then using vlookup to conver them into
real name.

For example;

Student number /Name
123 999 Eric Mary

When i type 123 in Col 1, col 3 show "Eric", type 999 in Col 2, col 4 show
"Mary". So, i know they are sharing the room.

But how can i alert the next entry , i can not type 999 again, as Mary has a
room mate already ?!

Can anyone help.. as when you deal with a list of 90 undecisive classmates

thanks
Eric