Polymorphism Exercises

1. Share with your neighbor(s) what is polymorphism and why we would want to use it.
2. Name the four essential ingredients to call a polymorphic method
3. Write a SHORT C++ program that has a polymorphic method named print() that prints out its class name. Clearly label (with C++ comments) each of the four essential ingredients for having a polymorphic method call:
   1. Inheritance
   2. Virtual method (base class)
   3. Virtual method overridden in derived class
   4. Pointer or reference of the base class type, but pointing to/referencing the derived class
4. Can a constructor be virtual? Share your thoughts about this with your neighbor(s).
5. Without compiling the code, determine what the output of the following main function will be.

   #include <iostream>
   using namespace std;
   
   class Base {
   public:
       Base() {}
       virtual void A() { cout << "Base A\n"; }
       void B() { cout << "Base B\n"; }
   };
   
   class One : public Base {
   public:
       One() {}
       void A() { cout << "One A\n"; }
       void B() { cout << "One B\n"; }
   };
   
   class Two : public Base {
   public:
       Two() {}
       void A() { cout << "Two A\n"; }
       void B() { cout << "Two B\n"; }
   };
   
   int main() {
       Base* base0 = new Base;
       Base* base1 = new One;
       Base* base2 = new Two;
       
       base0->A();
       base0->B();
       cout << endl;
   
       base1->A();
       base1->B();
       cout << endl;
   
       base2->A();
       base2->B();
       cout << endl;
   
       return 0;
   }