rA column has many many rows and most of them are empty. Those having
figures look like
(100)
(99)
(98)
(4)
(3)
(2)
(1)
0
10
98
99
100

As you can see, some of them offset each other and the result of
offseting is zero. And the 10 = absolute(sum(-1,-2,-3,-4). What I need
from this procedure is a list showing 10 and its counterparties.

My thought is that first step is a fill an array with these non-blank
figures. Next step is to offset those "offsetable" to get rid of them.
Third step is to list those "un-offsetable".

Any comments or code to share? Thanks a lot!

H. Zhu