As you're just new with hashes of arrays (and presumably other complex data structures) you should find Data::Dumper helps you to A) define data structures in one hit and B) clearly see what your data structure contains:

#!/usr/bin/perl

use strict;
use warnings;
use Data::Dumper;

my %hash;
push @{$hash{"3"}}, "apple";
push @{$hash{"2"}}, "pear";
push @{$hash{"5"}}, "orange";
push @{$hash{"3"}}, "grape";
push @{$hash{"2"}}, "icky pineapple";

print Dumper(\%hash), $/;
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(note the backslash in front of the % in the print statement) which would give you:

$VAR1 = {
          '3' => [
                   'apple',
                   'grape'
                 ],
          '2' => [
                   'pear',
                   'icky pineapple'
                 ],
          '5' => [
                   'orange'
                 ]
        };
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Just change the $VAR1 to %hash and the {} to () and it's done for you :o)

my %hash = (

    '3' => [ 'apple', 'grape' ],
    '2' => [ 'pear',  'icky pineapple' ],
    '5' => [ 'orange' ]

);
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