perl哈希嵌套和引用的使用

数组，哈希嵌套

数组，哈希的引用

1.哈希的嵌套和引用

%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";
   
}

输出结果

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

2.数组的嵌套和引用

@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";
}

输出结果：

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