use strict;
use Data::Dumper;
$Data::Dumper::Indent = 1;

my %thingy;
my @lines = ... # insert your data here

for (sort @lines) {
   my ($type,$stuff) = $_ =~ /([A-Z]):\s+(.*)/;
   my @parts = split('/',$stuff);
   push @parts,'';
   my $str = q|$thingy{'| . shift(@parts) . q|'}|;
   for my $part (@parts) {
      $str .= qq|->{'$part'}|;
   }
   eval $str;
}

print Dumper \%thingy;