Hello community

I have several pairs of shoes to put in boxes of 10 pairs
I need to sum each line to know when it reaches the 10 pairs.

If adding the lines exceeds the 10 pairs, I have to save this value (remainder) to sum to the next line Quantity and then check again if the result is bigger than 10, if not , i must continue to sum with the next line quantity until you reach the 10 pairs, and so on.
That is, I have to make the maximum of boxes of 10 pairs, what remains will be less than 10 pairs, soon it will go in a different box with less pairs.

Someone could give me a small example to try to do this, for example with a VFP cursor.
Many thanks
Luis