I have some employee data from two different sources (on two separate tabs).

On 3rd tab, I'd like to show if the data is on sheet A , but not on sheet
B, and vice-versa. E.g.

Sheet A
Employee ID Name
12345 John
78910 Mary
45678 Joe

Sheet B
Employee ID Name
12345 John
45678 Joe
77777 Jill


So I'd like to have in Sheet C something to the effect of:
Mary is in sheet A, but not B &
Jill is in sheet B, but not A.

Another thing I'd like to be able to do is:

One of the sheets shows days off as follows
NNNNYYN Y's meaning they're off Wed & Thurs
the other sheet shows WedThu as their days off
Can I also get someting to indicate that for that particular employee ( ID)
if NNNNYYN meaning off Wec & Thu on one sheet, but shows FriSat on the other,
to produce an Alert such as "day offs don't match"" ?

Much thanks,

Steve