showing how virtual functions can make pseudo type introspection

class_test.cpp

#include <iostream>
#include <vector>
using namespace std;

class Animal
{
public:
	virtual void sound()
	{
		
	}
};

class Cat : public Animal
{
	void sound()
	{
		cout << "meow\n";
	}
};

class Dog : public Animal
{
	void sound()
	{
		cout << "woof!\n";
	}
};

int main()
{
	vector<Animal*> a;
	Cat a_cat;
	Dog a_dog;

	a.push_back(&a_cat);
	a.push_back(&a_dog);
	
	a[0]->sound();
	a[1]->sound();

	return 0;
}

/*
	outputs

	meow
	woof!
*/