I think he just interprets three spaces as two spaces that will become one, and one space that will become nothing.

seems like you have an extra whitespace character at the end of your output

Hi. Please say which language you are using. Also, please use markdown tags to format codes or logs, or it may be unusable (see there: https://docs.codewars.com/training/troubleshooting/#post-discourse ). For example, trailing or consecutive spaces don't display properly, but it seems your answer contains an extra trailing space.