Use private-class members inside other private-class members
===

I am fairly new to C++ and am wondering if I am allowed to do the following:

    class oFoo{
      ...
    }
    
    class Foo{
       int x;
       oFoo* oArray[x];
     public:
       Foo(int xVal);
       Foo~(); 
    }

Am I allowed to use x as the bound for the array of pointers to class oFoo?? 