Which code, inserted at line 19, generates the output "23"?

#include

#include

using namespace std;

class A {

int x;

protected:

int y;

public:

int z;

A() { x=1; y=2; z=3; }

};

class B : public A {

string z;

public:

int y;

void set() { y = 4; z = "John"; }

void Print() {

//insert code here

}

};

int main () {

B b;

b.set();

b.Print();

return 0;

}