Hi,

I can have the number 1 in several cells in a range of cells A1 to Z1, but
it is always filled starting from cell A1 and gradually to the right. May
also skip some cells.
Ex.
A1 to C1 may be blank, D1 is 1, then E1 to J1 is blank, then K1 is 1, and so
on.
I need a formula which adds up these 1s to the last position where a 1 is
found.

Summing up the cells till Z1 is not an option, since later, in another
formula I will find the sum of all the 1s AFTER the last 1 which was summed
up in the first formula.
This second formula will be relatively easy after I get the first formula.

I hope this was well understood.

Thanks in advance guys.
Berj