I've got a terrible solution in progress for this challenge, and I cannot figure out how to make it ignore empty rows/columns to avoid reducing an empty list. I'm wondering two things: is there some cleaner way to get the indices between and including the first and last truthy values that doesn't involve r/, and is there some way I can actually get this to apply only to lines containing at least one truthy value?

tio.run/##y0rNyan8/…

S€T$ seems to give the right indices, but for some reason it's not actually stopping the link from being applied to the excluded indices

...¦ maps and then selects, doesn't it

oh it was just the multiline strings

That's actually a really neat solution!

I can't see fast golfs, I'll think about it more though