If this is the sole task of your perl script, then note that you can run any of the above solutions right from the command line (see perlrun for more details):

perl -pe 's#.+/##' file.txt

perl -MFile::Basename -pe '$_=basename $_' file.txt
perl -MFile::Basename -ne 'print basename $_' file.txt

perl -ne 'print ( (split("/", $_))[-1] )' file.txt
perl -F/ -ane 'print $F[-1]' file.txt

cut -d/ -f6 file.txt
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