Global Variable

In my Main.php I want to have $seconds = 0; and then from my seconds.php file be able to get this variable and add 1 to $seconds ($seconds++, I cant figure out how to do this so any and all help is appreciated!

Now I'm getting this error on the console :/

Code:

22:36:57 [NOTICE] ClassCastException: "Object of class CrazedMiner\Main could not be converted to int" (E_NOTICE) in "/src/pocketmine/scheduler/ServerScheduler" at line 120

That¿s because you're doing something wrong in your code xD

Why not just use time()?