Extract one unique value from three

I have three values in three cells A1,B1,C1

Like this

1...2...2
2...3...2
2...1...1

In each case there will be one unique value and two the same - although the unique value may be in any one of the three cells.

How do I ask - 'return the unique value from these three cells'.

Thanks.

Or try:

=IF(A1=B1,C1,IF(A1=C1,B1,A1))

Excellent, both.
Many thanks.