help needed: how to update php values?

Hi

I'm php newbie. For example, I have a php file like this:

php Code:

<?
$value1="content1";
$value2="content2";
?>

Now I want to create a HTML site with 2 input forms allow me change the values (content1, content2) without edit above file manually. I can enter new data and click update button, then it will update new values of above php file.

How do I create this file? There are no SQL DB or complicated functions.

Thank you