PHP join two variable names

Question

I have a php script that gets a $_POST to decide which array to return. Ex:

$n = $_POST['n']; // 1, 2 or 3

$a1 = array ('something', 'something else', 'another thing');

$a2 = array ('something 2', 'something else 2', 'another thing 2');

$a3 = array ('something 3', 'something else 3', 'another thing 3');

now I want to get the array that corresponds to the $n value, let's say "2".

How can I say echo $a . $n to get $a2

Thanks.

Answer 1

${'a'.$n} gives you $a2 if $n is 2.