Browser displays '$system_path = ../system; $application_folder = ../application'

Hello,
My project works before in Ubuntu, but recently I moved it to Mac. After configuring Apache, the website finally doesn't give any errors. But the browser only displays:

Code:

$system_path = '../system'; $application_folder = '../application';

No matter what parameters I append the url, it gives the same result like above. When I installed CodeIgniter in Ubuntu, I got the same problem, eventually I solved it, but I forgot how to solve it. Please help me.