Private Virtual Functions ???

Q: If base class has public Virtual function and Derived has private function for same virtual .
Which function is called by base PTR pointing to derived ??
Ans : derived will get call , though it is private at derived
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Output :
./a.out
derv1::f
derv2::f
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Q What if I have derived PTR and its pointing to Derived object and i call for VIRtual function??
Ans :  This will not get compiled 
 error: `virtual void der1::f()' is private