my $search = "red";

my %fruit = (
   'apple' => ['red','green'],
   'kiwi' => 'green',
   'banana' => 'yellow',
  );

my %idx_fruit = (
    'red'    => {'apple' => 1 },
    'green'  => {'apple' => 1, 'kiwi' => 1 },
    'yellow' => {'banana' => 1},
  );