#! /usr/bin/perl

use strict;
use warnings;

sub display
{
        my $ref = shift;
        foreach my $key (sort keys %{$ref})
        {
                print "$key = [";
                foreach my $key1 (@{$ref->{$key}})
                {
                        print "$key1,";
                }
        print "]\n";
        }
}

my %hash1;

$hash1{'frog'} = ['jumps','swims','slimy'];
$hash1{'dog'}  = ['barks','swims','hairy'];

display(\%hash1);