Check if user is enrolled in specific Moodle course

On a Moodle-enabled site, I want to give users some coupons. I made it to check if the user is logged in, but I also want to check if the current logged in user is enroled in specific course (an array of 3 course IDs). So far I tried with `$USER->currentcourseaccess` or `$USER-> lastcourseaccess`, but they don't do the trick. So, how can I check if the current logged in user is enrolled in specific Moodle course? --- **Edit:** The site uses _Moodle 2_.