#include <iostream>
using namespace std;

class Base
{
private:
	const int aNumber;
public:
	// CTOR
	Base( const int _aNumber ) :
		aNumber( _aNumber ) {}
	
	// check value	
	int getNumber() const
	{
		return aNumber;
	}
};

class A : public Base
{
public:
	A() : Base( 50 ) {}
};

class B : public Base
{
public:
	B() : Base( 80 ) {}
};

int main() {
	A a;
	B b;
	
	std::cout << "A: " << a.getNumber() << std::endl;
	std::cout << "B: " << b.getNumber() << std::endl;
	
	return 0;
}