The regex explainer would have told you something to help you:

print "japhy" =~ /(.)+/;  # prints 'y' ONLY
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Here's what explain has to say:

----------------------------------------------------------------------
  (                        group and capture to \1 (1 or more times
                           (matching the most amount possible)):
----------------------------------------------------------------------
    .                        any character except \n
----------------------------------------------------------------------
  )+                       end of \1 (NOTE: because you're using a
                           quantifier on this capture, only the LAST
                           repetition of the captured pattern will be
                           stored in \1)
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japhy -- Perl and Regex Hacker