use strict;
my $hash_ref = {
	key1 => "value1",
	key2 => "value2",
	ary1 => [
		{ ary_key01 => "ary_value01", ary_key02 => "ary_value02", },
		{ ary_key11 => "ary_value11", ary_key12 => "ary_value12", },
	],
};

##</code><code>##

$hash_ref -> { key1 } = "new value1";
$hash_ref -> { key3 } = "add value3";
$hash_ref -> { ary1 }[2] = { ary_key21 => "ary_value21", ary_key22 => "ary_value22", };

use Data::Dumper;
print Dumper($hash_ref);
exit;

##</code><code>##

$hash_ref -> {
	key1 => "new value1",
	key3 => "add value3",
	ary1[2] => [{ ary_key21 => "ary_value21", ary_key22 => "ary_value22", }],
};