Find common dates in two lists

[Bellave_Jayaram]

I have two lists of dates, checkins and checkouts, and I am trying to find common dates but it doesn’t seem to be easy/possible. Anyone got any tricks or suggestions?

Thanks.

[Steve]

Given lists A and B:

(A - B)

gives items that are unique to A.

(A - (A - B))

gives items in A that also occur in B.