%hash = (

'group1', {'fruit', 'banana', 'drink', 'orange juice', 'vegetable', 'cauliflower'},

'group2', {'fruit', 'apple', 'drink', 'apple juice', 'vegetable', 'lettuce'},

'group3', {'fruit', 'orange', 'drink', 'red tea', 'vegetable', 'tomato'},

'group4', {'fruit', 'pear', 'drink', 'red wine', 'vegetable', 'cucumber'}

);

for $key (sort keys %{hash})

{

   print "$key:\n";

   my $ref=$hash{$key};

   for $attr(sort keys %{$ref} )

   {

     $Val=%$ref{$attr};

     print "$attr\t\t$Val\n";

   }

    print "\n";

}

group1:

drink           orange juice

fruit           banana

vegetable               cauliflower

group2:

drink           apple juice

fruit           apple

vegetable               lettuce

group3:

drink           red tea

fruit           orange

vegetable               tomato

group4:

drink           red wine

fruit           pear

vegetable               cucumber

@fruit = ("banana","apple","orange","pear");

@vegetable = ("cauliflower","lettuce","tomato","cucumber");

@drink = ("orange juice","apple juice","red tea","red wine");

@list = ([@fruit],[@vegetable],[@drink]);

$ref = $list[1];

for $attr1(@list)

{

   print "@$attr1:\n";

   for my $attr(@{$attr1})

   {

      print "$attr\n";

   }

   print "\n";

}

banana apple orange pear:

banana

apple

orange

pear

cauliflower lettuce tomato cucumber:

cauliflower

lettuce

tomato

cucumber

orange juice apple juice red tea red wine:

orange juice

apple juice

red tea

red wine