pRED* | NZ: you can't remove a global variable from memory once it has been allocated. There's nothing horrible about global variables, they're much more hospitable than the plague even, get used to them.
The Specialist: from experience, I would say that every variable, when created, if not assigned a value, is assumed a value of 0 (or false). You don't need to assign it anything specifically, even if it's local.
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No longer around. Thanks your support, everyone! As always: