How to count cells

[Maci3j]

Dear readers,

so here we have 3 different systems. Is there a good way to count the number of all cells that are different? So the result of the formula will be 3.
This is how my table looks like:

system

01ms01

01ms01

02ms01

02ms01

04ms03

<TBODY>
</TBODY>

 

[VoG]

Try

=SUM(IF(FREQUENCY(IF(A2:A10<>"",MATCH("~"&A2:A10,A2:A10&"",0)),ROW(A2:A10)-ROW(A2)+1),1))

confirmed with CTRL + Shift + Enter, not just Enter.