Ok, the "interesting" thing is this expression is that 5 is accepted as a variable identifier although it does not meet the requirements to be one. The fact that the expression evaluate to a result that turns to be correct is not so relevant.
I think you mean "pointer type", not "variable". 0xblah could very well a be valid pointer value.
Anyway, Array subscripting (brackets) is not an operator in C. It is just syntactic sugar. This is different from C++ (but even in C++, C compatibility is maintained for primitives) .
