my %values = ( "apple"  => "1",
               "pear"   => "3",
               "orange" => "3",
               "melon"  => "2",
               "grape"  => "2");

##</code><code>##

Level 3:
Pear, Orange

Level 2:
Melon, Grape

Level 1:
apple

##</code><code>##

my %hash = (
  1 => ["apple"], 2 => ["melon", "grape"],
  3 => ["pear", "orange"]
);

$hash{1}[1] = "pickle";

print "Level $_\n@{$hash{$_}}\n\n" for reverse sort keys %hash;