Why is my code rejected? I believe it's 💯% correct! (SOLVED)
It's from a challenge "extra terrestrials" https://code.sololearn.com/cmG14rRZ7v1c/?ref=app
What happens if len == 0?
Not all characters are printable, so even though you can't see the difference, the computer can.
Hah 😅 Dennis, you nailed it, I didn't even notice!