Sorry. Better now?

Can't see your comment because I haven't solved the kata yet.

Thanks those who have helped explain the kata!
@arssonist, I can't really give any explicit hints or it will ruin the fun of completing the kata... ;)

Thanks, glad you enjoyed it!

Without seeing your code I guess that you access an array or vector out of bounds.
If you keep having problems, you could post your code (and mark as spoiler).