Good day,
I would like to get help on the following.
A B C D
19:00 16:00 21jul 21jul
19:00 08:00 21jul 22jul

If it occurs that the date on C and D are the same and the time on B are
earlier than time on A it should be 0.
If time on date on C and D are the same an time on B are later than time on
A it should give the difference.
My main concern are if the date on D are later than C to get the difference
between B and A as it should be 13hours.