m/
\| \s* \[\[ (.*?) \]\] \s* # song name
\|\| \s* \[\[ (.*?) \]\] \s* # artist
- \|\| \s* (\d+(-\d+)?) \s* # bpm
+ \|\| \s* (\d+(?:-(\d+))?) \s* # bpm
\|\| \s* (\d+) \s* # single beginner
\|\| \s* (\d+) \s* # single standard
\|\| \s* (\d+) \s* # single difficult