use strict;
use warnings;

use Data::Dumper qw( Dumper );

sub add {
    my $p = \shift;
    $p = \($$p->{$_}) for @_;
}

my $tree;
while (<DATA>) {
    chomp;
    add $tree, m{[^/]+}g;
}

print(Dumper($tree));

__DATA__
/var/www/data/stuff
/var/www
/var/www/data/misc
/var/logs
/var/logs/data