In my sheet, I have a range of data like this...

Class Total
500 20.0
500 12.0
500 35.5
502 28.3
502 13.7
503 19.3
504 21.4
504 30.7
504 14.5
...

In VBA, I need to copy the classes to an array, but with no duplicate.
I mean 500, 502, 503 and 504. How can I do that? Thank you in advance.