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#include <iostream>
using namespace std;
 
class Base
{
	public:
	virtual void print(){cout<<"Base virtual"<<endl;}
	void nonvirt_print(){cout<<"Base"<<endl;}
};
 
class Derived : public Base
{
	public:
	virtual void print() override {cout<<"Derived virtual"<<endl;} 
	void nonvirt_print(){cout<<"Derived"<<endl;}
};
 
void f(Base **base_arr) {
	base_arr[10]->nonvirt_print(); //base
	base_arr[10]->print(); //derived virtual
}
 
int main() {
	Derived *derived_arr[100];
	for(int i=0;i<100;++i)
		derived_arr[i] = new Derived();
	f(reinterpret_cast<Base*>(derived_arr));
	return 0;
}

prog.cpp: In function ‘int main()’:
prog.cpp:27:4: error: cannot convert ‘Base*’ to ‘Base**’
  f(reinterpret_cast<Base*>(derived_arr));
    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
prog.cpp:18:15: note:   initializing argument 1 of ‘void f(Base**)’
 void f(Base **base_arr) {
        ~~~~~~~^~~~~~~~

Standard output is empty