use strict;
use warnings;

my $INDENT=' 'x2;
my @aUnsorted= qw(/var/www/data/stuff
                /var/www
                /var/www/data/misc
                /var/logs
                /var/logs/data);
my %hVisited;
foreach my $sPath (@aUnsorted) {
  chomp $sPath;
  my @aName = split(m{/}, $sPath);
  for my $i (0..$#aName) {
    my $k=join('/',@aName[0..$i]);
    unless ($hVisited{$k}) {
      if ($i>1) { print '', $INDENT x ($i-1), '->'; };
      print $aName[$i], "\n";
      $hVisited{$k}=1;
    }
  }
}