how do I delete hidden rows or columns without doing it manually?

[Eastman22]

I have already hidden rows (from the subtotal function) and I would like to
delete the hidden ones (ex. level 2 in subtotals). How do I do this without
going line by line?

 

[bj]

select a blank column
enter 1 in the top cell
copy that cell
select the column
edit-goto-specal-visible cells
paste
select all format-cells-unhide
select the same column as before
filter-autofilter
select blanks
format-delete rows