Hi there,

I'm wondering how I'd be able to have a formula to calculate the number
of cells in a row which have appeared once and even though the value
appears many times in that row, I'd only count it as once. For
instance:

A
----
M
M
N
E
F
G
T
S
T
S

The result I'd want is 7, not taking into consideration the repeated
alphabets M, T and S. I wish to only count each alphabet once, not
matter whether if they are repeated or not.

Thanks!