How to correctly create a PHP condition in the rules in drupal?

Question

Drupal

I am creating a rule in the RULES module in Drupal.
There is a condition that if the [flagged-node:author] field is equal to [flagged-node:field_responsible_task], then the rule should not be executed.
I am new to PHP. Please tell me what should be between <?php and ?>
You need to use arg(0), but I don't understand what that means.
Thank you.

Answer 1

Use data compare, click from UI