Perl 5 (-p), 12 bytes
\$--{}}{++$\ The }{ pseudo-operator really comes in handy.
Perl 5 (-M5.010), 119 bytes
Provided by Nahuel Fouilleul in a comment
say 1#1say+1-yas This one is super boring, just using a comment like all the other non-golfing-language answers.!enilno ti yrT