#include <iostream>	    // for cout
#include <algorithm>	    // for clamp
using namespace std;

/*
 * The typedef keyword declares an alias for a type.
 *
 * Use it like this:
 *	typedef double cash;	    // Declare cash as an alias for double.
 *
 * It can also be used inside a class, to provide a type (if public)
 * or to provide a convenient alias (if private).
 *
 * Classes can also create a private typedef for std::string or std::ostream,
 * to avoid littering the class declaration with std::.
 */

// Store an even number
class Even {
  public:
    Even() : value(0) { }
    void set_value(int n) { value = n & ~01; }	// make it even
    int get_value() const { return value; }
  private:
    int value;
};


// Store an even percentage
class EvenPercent : public Even {
    // This example is trivial, but when we get to templates, the name
    // of the base class “Even” could be a LOT more complicated.
    typedef Even super;		    // Make convenience alias for base class
  public:
    void set_value(int v) {
	super::set_value(clamp(v, 0, 100));    // Call base class mutator
    }
};

int main() {
    EvenPercent ep;
    ep.set_value(7);		    // Should become 6
    cout << "Expect 6: " << ep.get_value() << '\n';
    ep.set_value(150);		    // Should become 100
    cout << "Expect 100: " << ep.get_value() << '\n';
    return 0;
}